The powerful second-rower is barred from turning out in Saturday's game between the two clubs because of a clause inserted in the deal that took him on a season-long loan to the Halton Stadium.
"I'm more disappointed for Gaz. I know he really wants to play. They must be afraid of him," said Betts. "Some clubs like to put (clauses) them in but, if I let a player go on loan, I wouldn't hinder his development by saying he couldn't play against us."
He added: "If I didn't want him, let someone else have him. It's not my call, it was part of the deal. It might have been a bit of a deal-breaker so we let them keep it in."
Hock, who missed Widnes' defeat by Catalan Dragons last Saturday through suspension, is still under contract at Wigan but was allowed to go out on loan after a major fall-out in the close season.
Betts will have the services of Australian back-row forward Hep Cahill for Saturday's game after he missed the trip to the south of France to be with his wife, who is expecting their second child.
"I made the decision that he shouldn't go," Betts said. "His wife is heavily pregnant and he needs to be around his family at this stage.
"It was the right thing to do because we were away for four days and, if something had happened, he couldn't have got back.
"She didn't have the baby but he'll play this week - it's a bit easier to get back from Wigan to Widnes."
Betts also expects former Wigan prop Ben Cross to face his old team-mates despite picking up a knee injury in his side's 46-14 defeat by the Dragons.