Love, love the mutant au. Can Jazz and mutant Danny communicate through something like sign language? Like, he can't talk because of his mouth but can he use his hands for basic signing? (Also does the blast through his chest ever heal or...?)
to answer your question: in theory, yes. however, there are a few factors here making this a little more difficult than it sounds
jazz would have to first teach herself the basics and shes stressed herself to the limit making learning a brand new language kinda hard
dannys new lanky limbs and spindly fingers make him pretty clumsy re: fine motor skills
if/when they can communicate with each other great! but jazz wants jack and maddie to understand as well and they dont believe (wont believe rather) that danny is.. danny. some clumsy hand movements that could just be this monstrous creature mirroring jazzs moves aren’t going to convince them so easily.. especially when they would have to rely on jazz to translate and they think shes...... compromised
danny cant write english words for a reason beyond just the motor control issue ;)
and finally (and this is the big one) there’s a time limit to figuring this all out that jazz and danny dont know about >;3c
jazz actually does have a very basic way to communicate but its limited (one knock for yes two for no, a classic) and danny a) is afraid of jack and maddie currently and wont talk to/about them and b) has a bit of a jumbled mind tbh
also to answer the second question: nope! always gonna be there~ other wounds heal and scar, but that one was so traumatic that dannys mind and body wont let it heal pink pearl style