Another thing to consider overall about fast approvals and why it is a rare thing...

With all the ageing baby boomer’s and the somewhat slow economy... older workers aren't able to find jobs they can do anymore and many have some sort of physical or health limitations.. they are all applying for SSDI also..

So the system is overloaded and has to scrutinize every application very closely..
And there may be a funding issue at some point in the future due to so many applicants & people already on SSDI. And a smaller workforce paying into the system..

One of the main questions you need to ask yourself... could you do some other job??
- If it fit with what would work for you?
perhaps if it was less stressful, and not on your feet a lot, and less interactions with many people?
Not necessarily teaching again, but something that is a better fit for your conditions...

I think the FCE may help to maybe find what you could do as well as what you can’t do..

This is just from my reading this forum often over the many years...so just my impressions..