It's funny how often people regret having made too many mistakes when playing organ in public.
These mistakes convert into panic.
Panic ruins the entire recital.
Let's step back for a second and ask why do mistakes happen?
Because we don't have enough self-control and confidence.
And confidence comes from knowing your piece inside out.
Can you take it from the middle? Can you take it from the end backwards?
Do you know how to start each segment of 4 measures not in the right order?
If you don't know, it's time you learn it this way.
Believe me, it will save your recital.