I tried it solo on routine with a level 6 character with Barrier and I didn't even get close.
That's why she said with an experienced team. No, I don't believe for a minute anyone who's never played MP before could take a Level 1 character with Level 1 gear and go solo the dragon.
It's not gonna happen. I've been playing DAIMP for 8 months and, frankly, I don't think I could solo the dragon with a Level 1 character with starter gear. Honestly speaking, I don't think I'd make it to Zone 5 to even face the dragon with that set-up.
But a new player can absolutely go Quick Match a Routine Fereldan Castle game, stumble on three other people, and if those three other people have been playing this MP at all (highly likely), then they can help you along to victory. And if you hate human interaction, I can almost guarantee you will hear nothing but silence in that lobby anyway because that's largely been my experience and seems to corroborate with many other MP players. So, you can easily think of those three other people as SP party members that you can't control and are running on the AI tactics.
This is also why a bunch of us are posting in here to be nice and offer help. Because if you get in with someone who's already been playing/knows the MP/has better gear, you'll be fine for beating the dragon. If you're on PS4 at all, I'd be more than happy to unlock the content for you. I did so for two folks earlier tonight and - despite neither having any MP experience to speak of - neither one even died tonight. They survived, one even seemed to really enjoy it, and when either got low on health, I tossed a healing mist grenade on them and all was well.
Easy peasy lemon squeezy.