Can a home care agency restrict us from ever hiring an aide we've previously worked with? Is this legal?

Recently hired a new caregiver agency and quit the previous one because they where not providing caregivers with dementia experience. One of the aides we really liked ended up quitting and wanted to come to the new agency we signed up with. So we brought her to them so that my mother can continue care with her. She is very good and the only one out of numerous aides that can handle her.

The new agency made us sign a contract stating if we leave the company and or any aide quits (our aide we sent to them in particular) we cannot not ever hire her. I find that hard to believe the company basically owns that person. Does it mean a lifetime or few months after we or they terminate. Is this legal?

The contract specifically states we cannot hire an aide that is currently or formerly worked for the company.

Please advise if this is legal

We brought the aide to them so we can keep her on my mother's case.

This is also under workmans comp and they are paying for service. We have signed the contract. Mary