Unless she knew the Triuumverate intended to throw her under the bus for her failure. Which she knew as a result of intercepting the correspondence with Josephine.
But your claim is that the letter was just a trick meant to deceive the Inquisition and deny involvement. There is no evidence that the Qunari punish people for failure. Missions fail sometimes. The fact Tevinter still stands is proof of that.
But let's assume they would have punished her. So what? Isn't it her duty to still report in and warn the Qunari of the danger Solas and the Inquisitor pose to the world? And isn't any punishment they deal better than being petrified by Solas? Well, at least a reprimand for failure would be. Demoted to athlok working in the kitchen, like Tallis was. However, declared Tal-Vashoth for going around the Triumvirate and getting Qunari killed for her own personal goals? Yeah, "awesome pose statue" would be a better existence than what the Qunari would do to her in this case.
And Grepher, I know you want to equate the Viddasala's failure with Tallis' screw-up, but they're really not comparable. Tallis caused a diplomatic incident that nearly caused war between Orlais and the qunari, but she still achieved one of the parameters of her mission: recovering the artifact she was sent for.
So did Viddasala then. She was able to feed lyrium to saarebas, which your side thinks was one of the mission parameters. Also, you think the mission was authorized. A simple failure to pull off an attack isn't the same as consciously going outside the scope of the mission, which is what Tallis did. What she did was far worse because it was her choice. Viddasala's success depended largely on the abilities of the southern nations. How can Viddasala be blamed for anything that was authorized? She tried to pull off an attack, the attack was repelled, which is constantly the case with Tevinter, so how is she at fault? Are all the Qunari on Seheron discarded for failing to take Tevinter?
Also, did Tallis even get the artifact? In any case, it was considered a failure because the mission was to get the artifact covertly.
The Viddasala's failure was total and absolute. She sank any possibility of an early victory for the qunari.
If authorized, then it was Par Vollen that sank their own chance. They appointed Viddasala alone. They wanted the ability to sever all connection with the mission. They refused to send the proper forces to ensure the mission's success. They allowed unskilled viddathari to be the vanguard of the attack. If anyone is to blame for the failure, it's the Triumvirate for dumping a convoluted plan on one agent whose role does not include commanding war efforts.
And even assuming you were right that she was to blame, so what would her punishment be?
The Darvaarad was compromised, countless qunari were killed, and Solas took back control of the eluvians. Dragon's Breath was a wash.
So? Most missions against Tevinter end in failure with many Qunari dead. Water comes, water goes. And the Triumvirate was able to disavow and deny, just like they allegedly wanted. So what's the problem?
Tallis got busted down to athlok for her partial failure. You know what was waiting for the Viddasala back in Par Vollen? If she was lucky, she'd face a public execution as the qunari's scapegoat, but in all likelihood, she'd be made a mindless labourer. The Qun waste nothing, after all.
For a simple failure against a strong opponent? Ridiculous.
What information could she possibly convey about Solas that would save her skin? "He's unstoppable; we are all doomed." Thanks for the report. We prepared a celebratory feast of qamek and 20-30 years' hard labour.
Solas can turn our people to stone with a mere thought. Recommend long distance surprise attacks from cover, or carefully laid traps. Solas can use eluvians. Recommend rigging eluvians to explode upon exit, or else shatter all eluvians. Also recommend working with the Inquisition to stop Solas before any other actions are taken against them, as Solas could be their enemy as well. Also, don't trust elves. Solas has his own spies among us. Be careful of the Inquisitor and his allies. They were able to mow us down and kill/release the ataashi. Here is a list of their abilities and attacks.
Seems like all very important information that would benefit her people, even if it wouldn't help her situation.
Who says the person who defeated a God-like Darkspawn Magister is the easier target?
The fact that this person can't petrify her with a thought. The fact that he is currently being killed by the mark on his hand. So Viddasala was no longer between a rock and a hard place. Solas was allowing her to leave, and the Inquisitor was in need of assistance. She could have left, or fallen back and waited for Solas to leave so she could kill the Inquisitor.
Us, players, because that's how we play it, but the Viddasala doesn't have to know it. Then add that she was very angry about the whole "total mission failure" (Dragon's Breath lost, Eluvians lost, her forces lost) and she probably wasn't in the best state of mind to calmly and coldly evaluate her options. She's the anti-magic fanatic, after all, more used to curbing magical threats under her thumb than suffering them.
She said she was no stranger to calamity, but the trouble posed by the Inquisitor defies comprehension. She should have been able to calmly evaluate the situation and go after the target she had a chance of defeating. Or else return to Par Vollen with information so the Triumvirate could formulate a strategy.
(Of course, if pop culture existed in Thedas, I'd say she watched too many cartoons in which a hero overpowers or at least causes some harm to the villain in a final moment of anger and desperation
).
In any case, you honestly think Viddasala would choose certain death over returning to Par Vollen with information that will benefit her people and perhaps lessen any punishment on her? You think she wouldn't take that opportunity to fall back and wait for her chance to kill the Inquisitor, or at least witness if he lives or dies from the mark?
No, the only reason she would dare attack Solas is because she knew she was unauthorized. She knew the Triumvirate found out. She knew being a statue with an awesome pose was better than being declared Tal-Vashoth for her unauthorized actions.