Personally, I'd be cautious and try to check anyway. This is something that airlines often mess up, although it should help a bit that MU and CZ are both members of the same alliance.

Is there some way that the OP can verify himself/herself that the ticket was properly endorsed? I assume it's all done in the reservation and ticketing (computer) systems of the two airlines with no ironclad written confirmation normally given to the passenger as proof that everything was done right. There's no indication that the passenger has paper tickets or that he/she even saw any agent in person about the change.