That is correct, however, they still have a quite a bit of time to file a civil lawsuit for the stolen goods that he has taken. Even if they all were returned, they would still have a claim for any damages to the items (particularly damages to the animatronic during removal if it is determined in the future to be connected to the same person) or damages incurred from loss of use while they were out of Disney's possession (like if they had to special order new custom suits, dresses, wigs, etc. to replace the stolen HM props in their rotation). It appears that they have a statute of limitations of 5 years to proceed on this from the time the cause of action accrues and that the accrual of that time is suspended during pendency of criminal prosecution (so they are not likely to be required to file a civil suit anytime soon and can take their time lining things up.
Also, the statute related to losses involving theft provides for treble (triple) damages and reasonable attorney fees and costs. I know what my hourly rate is and would suspect their attorneys would probably be at least as much if not more. I suspect all of this will not be cheap for him even aside from the criminal prosecution. Although, I also suspect that before taking the step of filing a civil claim the two parties' lawyers will probably at some point work out a quiet settlement for an undisclosed amount and that we will never ever know about it.
Here's a link to the set of pertinent statutes related to civil remedies for criminal acts if anyone is interested: