On what basis do you think that your job caused, accelerated or aggravaed this medical condition? OWCP is NOT going to approve your claim just because you believe it will help you get your job back. That's not how it works.
Because any OWCP claim that you file would be after your separation from employment, I would be surprised if the "reclaim your old job" rights under 5 USC 8151 would actually apply to you. If you have been gone longer than a year, it likely becomes even more problematic. However, disputes under 5 USC 8151 are decided by the Merit Systems Protection Board, rather than OWCP. I don't know if they have ever had a case that involves your potential fact pattern. It may be one of those issues for which there is no actual case law.
In other words, my opinion is worth about what you paid for it.