I´m sorry to hear about your problem and all the ones that had similar issues. Different options were presented already and I´m sure as everything evolves you will be able to find out the one that suits you better, I just wanted to add something else mostly from another point of view, this is also what I tell drummers that have no medical problems with their limbs but have a hard time playing the bass drum.
If you had read my previous posts most are around the same subject, "most drummers DON´T understand whats played on records or performances and try out nonsense techniques..."
Now, what i´m going to explain is not applicable to double bass drum technique, is for single pedal use ONLY.
Most drummers expend a lot of time practicing how to play 20.000.000 notes together as fast as they can when it is not the route. If you would be able to transcribe most great drummers you will notice that they just play 1 or 2 notes together with the bass drum at most. 3 in very extreme cases, but it is absolutely rare.
It´s about PLACEMENT, composition, etc. not speed. It´s about choosing the strategic points that make the pattern sound cool, hip.
So, as usual, the plan is to know music enough to be able to transcribe YOURSELF what the great drummer played to outline some rules for you to use, not to be fast. If you are fast it is a plus, granted, but the other is more important.
One note will be enough, in general you may need to play 3 of those SINGLE notes with the bass drum dispersed per 4/4 bar.
Remember, you usually have the freedom to shape rhythms and fills to showcase your best features, but you can only do that if you understand music.
So, indipendentenly of what you decide, think about this.
Good luck!