Without reading all of the above, I think your best bet is to make a play (given the circumstances) for your own row, meaning window and aisle seat with no one in the middle seat. Better yet, take the center row and get two aisle seats and therefore two aisles to access. Better still, upgrade to World Traveller Plus and avoid the middle seat altogether on the windows.
PS... With all due respect, especially given your age and health considerations, maybe international travel right now with a killer Chinese virus out there is a bad idea. I’m sure no one in the wedding party would hold it against you.