Can an employer force me to sign a Non Compete agreeement after I have been let go in order to receive my final check?

Was Project Manager for construction company. No contracts/paperwork signed before or during employment.
Owner/Boss quits Project/Company that we are working for in Alabama and brings us back to Oklahoma. During entire time in AL he didn’t pay OT to any employees or myself and would deduct hours on occasion.
While back in OK he was not able to keep us busy/work a full time week. I couldn’t pay my bills. I turned in Two Week notice and had plans to go back to Project jn Alabama and create my own crew to finish project he abandoned.
Owner/boss tells me not to finish out my 2 weeks, thus letting me go.
Refuses to release final check unless I sign a Non Compete agreement. And states that he will sue if I go to work in Alabama.
Does he have a leg to stand on?