Yes they are. I suspect he (?) needs some time. Give him a chance to settle a week or two with nothing but bare maintenance as suggested. I have had no problems converting the live feeders I have including a wild caught rescue. It takes some time to get the snake settled down, in two weeks offer live what ever it was feeding once the snake is eating then convert it, don't try too many things at once.

A rat is a rat and a 'happy' healthy royal will eat when it ready to.