Mistrial, maybe possibly. Even that's not very likely given the jury has the case at this point. Jump Kick Guy's identity and the compressed video aren't likely to be thy deciding factors to the jury. Mistrial with prejudice, if that was going to happen it would have already, so I wouldn't get any hopes up for that.
Something weird is going on with the jury, because this is a 3 or 4 hour deliberation, at most. This isn't a complicated case, nor were the jury instructions of which they requested 11 more copies. The prosecution filed a weapons charge that they admitted Rittenhouse didn't violate, yet they filed it anyway. That alone should raise reasonable doubt as to the burden of proof that rests with the prosecution, as any claims made by them cannot be trusted.