To be honest I don't see what issue the airlines would have with OML restriction for one pilot of a multi-crew aeroplane! However, in reality!!!!!
Especially now with new pilots being only Multi-Crew licensed too... But often emotions (that guy might collapse at the controls) overcome common-sense (that guy is OML, is being thoroughly checked and vetted health-wise and is probably in better shape than most of his peers)!
I'm about to regain (hopefully) my Class 1 after cardiac probs! 20+ years flying still doesn't mean everything is cushy! I do feel though that with the looming shortage that you'll find a job aviating somewhere and soon. Best of luck