It maybe possible the settings for tomcat have become corrupted.
Perhaps try looking at the com.jamfsoftware.tomcat.plist on your main server to see if anything is garbled. You may need to replace it or recreate it. Similar to this thread:
Hope that helps,
Princeton Public Schools
I'm surprised people haven't told you to stop posting on the forum and just contact Jamf Support. According to your profile, you work for one of the largest book publishers in the UK; surely you've got an active support contract and someone to call, even if it's basic 12x6 support only.
If Tomcat won't load, your first step should be to just reinstall the same version of Jamf Pro on top of the existing one. At least on Jamf Pro for Windows, it does not remove existing settings but "repairs" the installation instead. On Linux, you might have to uninstall then reinstall OR use the "manual installation" option. There's documentation for that here, too. I haven't installed Jamf Pro on a Mac except in a classroom setting and that was 5 years ago!