Do we know anything at all about pterosaur tongues? Have any ever actually been found? I've been doing quite a bit of research on pterosaurs, but I cannot find anything related to their tongues/hyoids.

This is something we actually know almost nothing about. There's a decent number of hyoids out there but they've only been looked at once even semi-seriously and no one has looked at muscle attachments, size etc. As it happens I'm helping a student who is looking at this area, so watch this space.