Without calling into question the broader possibility that malfeasance did occur, I don’t feel like this argument is particularly credible.
Suppose you were to engage in some form of straight up ballot stuffing? Why then would you make them bullet ballots? Why not vote straight ticket Republican? Straight ticket ballots are not unusual - even less so then bullet ballots, apparently - so you’d draw less suspicion, and you’d get the benefit of lots of extra down ticket votes.
If someone was going to cheat, what benefit would they gain from cheating this way?
The people below him matter because they enact his agenda. The fact that there is a cult of personality around Trump absolutely explains why real voters would vote that way. But anyone enacting a ballot stuffing scheme on his behalf would almost certainly understand that he needs cronies to actually do any of the things he wants to do.