You can try this: Migrate data from dead Gitlab-CE instance using only local files, backup corrupted! - #3 by kahshmick
If you look at the xxxx.git/config file it should show something like:
[gitlab]
fullpath = namespace/project
where namespace is the Gitlab group/namespace, and where project is the name of the repository. That will help you identify what hashed directory is what project. Then you can use the commands from the link to see if that will help you recover on the new server.
However, you have two big problems here. First, you don’t have any backups of your server which would have saved you all these problems in the first place - so you need to make sure you have backups. Second, why did you uninstall Gitlab and then install it again? What did you think that would achieve? That is a destructive action which is what destroyed your install. You shouldn’t have done it.