Infinite regress and debunking karma

[Anomalocaris]

Karma is not a theory because there is no evidence for it and no testability in it.

But in its lack of rigor is also its ability to find ad hoc ways to avoid the objection you posed.

Bob may have done a misdeed, but the effect of his misdeed may be delayed and the suffering it causes to make it an misdeed is not experienced by his victims until he himself has been karmically punished for the misdeed.