Well, Honestly, it doesn't come down to worshpers and their petty clashes.
If I where to worship Lamashtu (this is William BTW), I would obviously have to deal with obeying an asmodian preist. However I do it in the name of the mother if monsters, and plan on killing the preist later and painting the walls of his temple with his blood and using it to Sommon some demons.
Anyways, I'm still going for a hidden preist, and probably plan on keeping her religion hidden from the others in the group, Although who she worships will eventually become obvious at later levels when she becomes a Demoniac.
When it comes to gods, I think Lamashtu tends to not care who her followers work with, as long as they sew ruin and destruction, the standard watch the world burn ideal.
It's Asmodeus that cares. :P
Racial Variant: 1d100 ⇒ 51- Speak to Birds
Same: 1d100 ⇒ 9-+2 Cha(taking this on top of my normal +2 Cha :P)