I think most of these things are a he said/she said debacle. No way to know the exact truth. The Schindler's are lifelong practicing Catholics (and devout by all accounts) so I doubt they would have encouraged him to date while married to their daughter. That is a serious sin for Catholics. Either way, I don't pay much attention to the details, I just look to see what happened and what both parties have done - not what they have (supposedly) said.
Ahem. You have not read any court documents I gather. Not that I blame you. They number in the thousands of pages and I've forgotten half of the little I did read.
BUT, Terri's parents testified under oath and cross examination that they ENCOURAGED Michael to start dating again. He even, with their encouragement, introduced some of his girlfriends to them.