oh... , you are so dangerous. this is an experiment of "the in between", i do suspect astarion will agree the experiment.

astarion -- "oh, my god, no, my... oh..."

Of course I would only try it if he wanted it, it would also not work otherwise. Though the whole situation would be a bit ... awkward, especially when Tav is romancing Astarion. But hey, they already had a discussion about how they would kill each other. This would definitely be the weirdest romance I had in a game so far, but I like it.
Your last sentence made me think of a "reverse bite night" situation, where Tav sneaks up on Astarion. "It's not what it looks like, I swear!"

But no, my Tavs are too kind for something like that.
If the True Ressurection spell would be available, this would also be a quite costly option, I wonder where we can get diamonds worth at least 25,000 gp. A sprinkle of holy water should be easy, and we would need a cleric or a druid, so most likely, we would have to drag Shadowheart or Halsin into this mess.
As for the discussion about Gale or the possible goals or intentions of our companions in general: I think the dialogue options each companion gets when standing in front of the magic mirror in Ilyn Toth's lair are very interesting. I know, these are just
options, but the choices are quite revealing, I think (and I like that every companion gets three options, except Lae'zel, who is very focussed on her two primary goals).
Silver/ was so kind as to link the screenshots in another thread:
Major spoiler:
https://www.reddit.com/r/BaldursGate3/comments/jppkbd/companions_at_the_magic_mirror/Personally, in this discussion, I do not equal "trust" with liking a companion or agreeing with them; for me, it is more like "do I know where I stand with them?"
This is more easy with Lae'zel, who is very direct, and also Astarion (even when he is trying to be a bit more manipulative, it is so obvious I can hardly call it that at all). They do not even try to be "nice"
