Interesting, I wonder if something else on the card is damaged.

I just pulled my IIe cards out last week (I have two.) The LCIII that I tested them with has leaked caps that I have not replaced yet, but seems to be working fine.

Both cards were in good shape when I put them away years ago, now after being used, the caps are leaking. :'( One card has some weird video issues and does not display certain colors correctly. The other card will only do B&W video. I suspect that the leaked caps are the cause but I haven't had time to replace them yet.

Clearly that may not be your issue though. Are you 100% certain that the replacement caps were installed correctly? Not backwards?