Help cleaing up AWS LB Cognos issue

[strat]

Hey, so I have a few request here. I've recently inherited a cognos system that was being maintained by another user. Well that user has abruptly left the company and I need some help.
They were setting it up to go through an AWS ALB and for the most part it's working correctly. But with some of the reports they're getting an error 404 when they click the link.
We have Server1 and Server2. Server1 sends the URL link1.app.domain and it works fine. Server2 sends link2.app.domain and it fails. But if we take that URL and manually change it to link1.app.domain then the URL works.

If anyone has any way to fix this please let me know. I'd like to have Server2 send the correct URL.
Also, what are your recommendations for learning material on cognos?