"Correct me if I'm wrong, but a D1 to D1 transfer requires sitting for a year regardless of permission."
You are correct, but there are exceptions to the rule:
"If the student-athlete has never transferred before from a four-year school and meets academic requirements, that student-athlete might be able to use the one-time transfer exception (except in baseball, basketball, men’s ice hockey or football)."
Another is if a school drops a sport then students are then allow to transfer without sitting out a year.
Obviously, Chris doesn't meet the exception rules.