I think you’re overblowing fumbles for quarterbacks. They fumble more than any position for obvious reasons. Kyle Allen is up there with Minshew, Cousins, Goff, Watson, and Dalton for fumbles right now. All these guys have pretty bad offensive lines. Allen has also only fumbled once in his last two games. The difference here is that Kyle Allen has 0 interceptions.
Allen does a much better job of finding his outlets than Cam. He spreads out the defense more than Cam which helps McCaffrey get more space to operate. With Cam in, the defense just has to focus on the backfield instead of worrying about the receivers.
If Kyle Allen keeps winning games I think Cam should be saved for later. Cam could come back when fully healthy instead of being rushed, which is perfect for the Panthers. Cam has more talent but if it ain’t broke don’t fix it.