I don’t think he should - at least more than once. Her most vulnerable position is the Border Czar issue. But the moderators - whomever they choose - will NOT let it become the prime issue of the debate, especially if she starts off handling it badly.
the earlier the better - she is known for not studying her prep materials so her knowledge on major issues is likely to be talking points, with no depth or evidence of having processed all angles of a position. DJT should dictate moderators who will mine this deficiency. his agreement w/Joe is no longer binding.
Big mistake to add to her rapid coronation
Definitely NO debates until she and her VP are formally nominated.