Unfortunately, I know that problem...
Lucky for you, it's just the 2 inside retainers which are broken. On mine, it was a center latch one as well as both for the visors. Plus the rest of them were starting to split. anyhow, I wrote up a DIY on how to R&R. Pretty simple job once you get rolling.
File attached w/ details
Good luck and feel free to PM w/ any questions.
