Please don't mind me asking, but can you confirm that you've started the VMware-Migration-Assistant.exe "As Administrator" on the vCenter Server?
You can find it on the vCSA's ISO image (Directory: migration-assistant).
In your initial screenshot you have three entries for this port. The first two are likely related to the Migration Assistant.
What about the third one "My port"? Please ensure that the port is not in use by something else.