Thanks for the suggestion jsalmeron,
I looked through the offending files and the config files you suggested. Everything looked fine, no signs of any corruption.
I then overwrote the entire vendor directory and copied the configs from a much early VM backup (I did try to restore from this backup then ran back into the startup issue mentioned before aka my backups are also dead). The same syntax error remained.
I have since decided to give up on restoring or fixing this VM. I'm in the process of resetting up all the repositories and re-pushing the commits from other team members machines.
Due to only using Gitlab for a few months now code loss will be fairly minimum I hope.
I will use a scheduled backup within the ubuntu environment itself rather than backing up the virtual machine on the host os.
Thank you for trying to help me with this issue.