Aphantasiac here, happy to discuss or answer any questions
how is your proprioception? https://en.wikipedia.org/wiki/Proprioception e.g. if you put your hand behind your back and move it up and down randomly, then stop suddenly, can you tell if it's stopped closer to your legs than your neck? i cant think of a better test for it :( (clinicians?)
I can also draw what I can't see pretty well from memory.