Eliminate simple first. You are probably crushing bees during inspection. You yourself said the next couple of days after inspection. Leave them alone and see if you see the same hauling out of brood. Eliminate the you first
As a newbee I know it is hard.
Does everything else look like it is growing fine? Are you getting burr comb in bee space being filled with drones and tearing it apart during entry. Chewed up brood... well they have to pull the dead brood out of the cell if it were caused during inspection. If I saw it continuing to happen other than after inspections then I would begin to suspect something else.