Regardless, a loyal Ben-Hassrath would be obligated to report and potentially apprehend Vashoths and Tal Vashoths.
I don't think so. Vashots aren't on the same level of the Tal-Vashoth in the eye of the Qun, because they don't fight it. I don't think that qunari hunt Vashots, but I guess we'll know more with Ib.
Literally everyone who isn't in the qun is a vashoth or tal-vashoth. Sera is a vashoth, dorian is a vashoth, alistair is a vashoth. You don't need to report when you go to a country where your religion hasn't spread "Oh god no one here is our religion I have to apprehend everyone"
Nope. A Vashoth is a qunari that left the Qun but has no ill intentions towards it, so they'll generally leave Seheron and Par Vollen.
That's the main difference between Vashoth and Tal-Vashoth. The latter are against the Qun and fight.
People that never were members of the Qun are generally called bas, if i recall.