How to claim passport back in a criminal investigation with no charges pressed?

My husband works in a semi-government company in Dubai. Due to certain suspicious activities, the company has started an internal audit and found some financial scam against his manager.

Later on, his manager absconded. The company has terminated my husband giving the restructuring as a reason. Though till time there are no charges against my husband, the employer has taken his passport.

The employer is saying as he is the witness and passport is with the company, as soon the police tell him to release the passport he will hand it over to us. He doesn't know how much time the police will take.

It's been 3 months without salary (one-month suspension and 1 and a half month termination).

Now, can the employer put any criminal charges against us after termination if we are going to file a case against him in the labor dept.?

We have no idea whether the employer has done a police complaint or not.

Please note we have already taken a police clearance certificate and went to the police station 2 times and found no criminal charges against him.