I've been struggling with this for some time, so apologies for the cross post.
I have a simple multisite set-up with mapped domains and SSL (using the wordpress https plugin). Each mapped domain has their own security certificate purchased. I have installed them and set the https plugin to use the SSL for the correct domain.
SSL is working perfectly for one domain - and it's a disaster for the other. The one which doesn't work is constantly redirected to http. I can't enter secure filters because they get zeroed out. And the HTTPS domains in the network admin all keep changing to the default url as soon as they're saved.
I'd love some guidance on how to fix this, if anyone's encountered this issue before or has some troubleshooting suggestions.