BWBShari,
This is how I would approach things if I were in your situation, aside from pulling him out and homeschooling, which is pretty much what I did!
I would remind them that retention is only appropriate if the problems he is having would be remediated through further instruction in the same grade.
Sensory and language processing disorders, convergence insufficiency, and other functional vision issues are not due to insufficient academic instruction, and will not be improved by retaining him in grade. Repeating phonics instruction will not help him be able to see the words to read them. Keeping him in a bright, noisy, K classroom will not help reduce his sensory processing issues. None of his issues are the result of starting school too soon, and they won't just go away because you make him wait another year to advance.
Appropriate therapies from the relevant specialists might improve things eventually, but until then, accommodations and modifications would be a more appropriate way of ensuring that your child has an appropriate education that he can derive educational benefit from. He will not derive educational benefit from repeating material that he already knows.
If you can "broken record" that through the whole meeting, they might get the idea.
Best of luck. You are in my thoughts.
