If they knew, and didn't bring this to the attention of the authorities, aren't they complicit???? Is Jerry (not saying he's innocent or quilty) wilingly taking the fall for a "family problem" and feels his grandchildren are in no more danger with him than with the grandchildren's families? This whole thing is a little odd.
Could have been one of those “too ashamed to talk about it till now” situations. (I’d ping Salamander except she has expressly asked me not to do so. She suffered from molestation too and this saga tears her up.) In which case it seems a bit cheeky for Jerry to ask, at least this quickly, to be visiting with those folks. I’d think he’d respect their reticence.