Yes.
DD8 is in vision therapy. Many of the exercises they are assigning her would help with the discrepancy between verbal and written spelling: hunt for things on a page, improve finger dexterity and motor planning, string beads in sequence. Even the tracking exercises would make sense: maybe when he reads it back, he is not *seeing* the letters in the order they are written because he is not tracking smoothly. This would correlate with extremely good reading in some ways, if he is compensating very well so that he understands the word correctly whether it's spelled correctly or not. DD's overall coordination has improved since she started VT, though she sometimes still falls out of chairs for no reason.
Knowing what I know now, I'd get a developmental vision assessment.