If you've not failed with all talk therapies and more than say 30-40 meds combos, including MAOI's, then you can't really logically give up on those approaches yet.
If you have failed with the above, have you considered mushrooms/LSD? That's what I'm trying next. They shouldn't be illegal so I have no problem with it and there's increasing amounts of data showing how incredibly effective they are for TRD.
I've tried Ketamine, ECT, hypnotherapy, 60+ med combos and nothing has worked. I've had TRD and TR OCD for 23 very long years.
Pete