There are unfortunately very rarely consequences for academic fraud. It's not just that we only catch a small fraction — mostly the most brazen image manipulation — but these cases of blatant fraud happen again and again, to resounding silence.
Ever so rarely, there may be an opaque, internal investigation. Mostly, it seems that academia has a desire to not make any waves, keep up appearances, and let the problem quiet down on its own.
The people doing the investigation have a vested interest in keeping it quiet.
It's like the old quote... "If you commit fraud as an RA that's your problem. If you commit fraud as the head of department that's the university's problem."
And occasionally a grad student who discovers academic dishonesty, and complains internally (naively trusting administrators to have humility and integrity), has their career ended.
I suppose a silver lining to all the academic fraud exposés of the last few years is that more grad students and faculty now know that this is a thing, and one that many will try to cover up, so trust no one.
Another silver lining might be that fellow faculty are more likely to believe an accusation, and (if they are one of the awful people) less likely to think they can save funding/embarrassment/friend by neutralizing the witness.
(ProTip: If the success of your dishonesty-reporting approach is predicated on an internal administrator having humility and integrity, realize that those qualities are the opposite of what has advanced a lot of academic careers.)
Ever so rarely, there may be an opaque, internal investigation. Mostly, it seems that academia has a desire to not make any waves, keep up appearances, and let the problem quiet down on its own.