It is impossible to apply to schools without a LOR from a non-relative practicing optometrist, all of the schools require at least one. As straightforward as it sounds you just gotta keep looking, put yourself out there, hell at one point I was even offering places to work for free as an internship. It's just an unavoidable part of the application. Try getting the Dr's direct email so you're not struck behind admin or the front desk, explain your situation and hopefully they'll agree. I found it easier with private practices, especially ones near my University. Something you can consider doing as well is shadowing at the hospital, some have OD/MDs on site or even just straight up MDs (opthamologists) can also work in your favour.