That would likely still be a redirect error because the software is directing you to one place and then your server is directing to another. When they finally meet, you're getting logged in as expected or hitting a CSRF key error because the key expired in that time (expected security behavior).
You would want to continue to investigate how your system is configured, especially with HTTP to HTTPS redirects. As you mentioned, the software is configured for HTTPS, there is no need to redirect this on the server side and it may be creating conflicts so disabling that would be advised.