Every single other online result is not helpful, the usual culprit is not having the right version of SSMS or permissions set up on the remote server but that is not the case here. I also can't just use SSISDB because I need to grab packages from the Integration service itself, and also I want to make sure this error doesn't mean there's general problems with the VDI's setup.
The ONLY difference between the two copies of SSMS are the version of the Microsoft Data Access component and the OS Version.
If Anyone's encountered this specific case where a working Integration Service that can be connected to without issues won't work on a new machine please share what was wrong. Apparently the Firewall settings on the new VDI are correct but I'm not so sure myself. I don't have access to change them however.