GenRight makes corners with recessed lights, I just installed a set last month, I also have a slight gap like you show in the picture. I used a little caulk and you can’t even tell it’s there unless you’re looking for it. I believe none of the corners will give you the prefect fit, and you’ll have the gap with most. Best fit would be aev as mentioned, which is what GenRight used to use and custom fit the recessed lights. Which is the reason wanted the GenRight ones. They have changed the design since last year and no longer use aev corners. I missed the last batch of aev ones by few weeks ffs.