Per an article I've quoted here before, the judge has noted that this circuit court has never reversed a decision for including prior acts. They have reversed one decision for not doing so. I really don't think it is a big concern.
"The judge acknowledged taking “a fairly deep dive” on rule 414, finding “pretty strong case law” to admit the prior acts of molestation as evidence. He noted that the 8th circuit has never reversed a case of admitting it, while one case was reversed for not admitting such evidence."
Judge calls for evidentiary hearing during Josh Duggar child pornography pre-trial conference
GhostwheelPyrrhonist