Why isn't the Sharepoint solution uninstalled?

Question

SharePoint

Good afternoon.
They asked for help with an ancient beast - Sharepoint 2010. It runs a small site that is periodically updated with a PowerShell deployment that has not changed for a couple of years. Deployment
steps:
1. disable features
2. disable solutions
3. remove solutions
4. install solutions
5. activate solutions
6. activate features
at one's own risk).
The reason for the error is generally clear - step 2 is successful, but in fact the solution remains in the deployed mode.
The delete command has not changed for several years:

Uninstall-SPSolution -identity $solution.Name -confirm:$solution.Confirm -AllWebApplications:$true

The set command contains the GAC flag, i.e. assemblies are thrown into the GAC, which has 4 assembly versions with the same identifier. In web.config, they also multiply. I did not try to clean it manually, because. I do not fully understand the logic of their connection.
If we delete the solution forcibly, then we are faced with the fact that the solution is installed, but not activated (Install-SPSolution is successful, we are waiting for the Job to finish). Calling Install-SPSolution again succeeds, but does not change the status of the solution - it is still not deployed.
If we try to execute Deploy through CA, then we get an error - it was not possible to install Featute, because. it's already installed. If you kill the Feature with the specified GUID, then there will be an error with a couple of other GUIDs - if you kill them all, then the activation is successful. The deployment script contains Feature data for deactivation, but if deactivation is performed several times, the "problem" ones continue to be successfully removed, while remaining in the farm.

I found a crutch that solves all problems - add the -Local flag to the deactivation and activation, and it seems like this is a solution for our installation from one server, but I would like to figure it out and not use crutches.
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There is a background from the user - there was a departure from the domain, he does not know the details, because. other people are doing it. The flight was fixed, but problems with Deploy started around the same time. I've checked every setting I know - everything looks like the problem is fixed. There is an error in the logs - I can’t find a server with a GUID, without details, but I found the server name in the database - it is very similar to the name of the current server, it looks like it was added to the domain with a new name, because the old conflicted.
Also in the farm settings there is a second server - the same server, but with an IP address instead of a Hostname, it has only one function - Email Notification.
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I will be glad to any advice, knowledge is outdated, but I would like to defeat the problem.