Without a tadpole, only Gale or maybe Wyll (not for all characters) would make sense to travel with us.
Astarion would have absolutely no reason to travel with us. For him, it would only be an unnecessary risk of someone finding him drinking blood.
He also has no hope that we will help him defeat his master, as he mentioned, his master could sneak into the camp and murder us all.
Asterion would have a reason, being vamp spawn. Just wouldn't be the tadpole.
True vampires are thoughtful beings, are aren't always just into random murders. just sometimes.
As stated more than once. The foundation is there.
What would that be the reason?
Asterion found a netherese scroll. used it. funny affect because he is only vamp spawn instead of full vamp.
immune to sunlight. will returned. master out of picture. as it is with tadpole now.
Or vamp master sent asterion to find something for him, and the party, being level ones, are so far below his notice that he told asterion he did not care, and to keep a low profile, but to find (we will put the nightsong here for a point, but does not have to be the nightsong)
Vamp master is not engaged in just watching asterion all the time. he has other matters as well. and if asterion caught and killed, he turns to ash. vamp master doesn't care all THAT much at the moment. Asterion is small fry, and you are small fry.
vamp might even be curious about tadpoles, and sent asterion out to interact with people with tadpoles.... but the vamp master does not want to be directly in contact with soomething that might go mind flayer. That would be a risk. But asterion in contact with it? sure. who cares. lets see what happens.
