Screens treated as "Span desktop across all monitors"

Hi everyone,
we are currently facing an issue at a customer site with display scaling when connecting to an RDS 2019 session through the Parallels Client.

Issue description:
- Screens are not treated individually, but as if "Span desktop across all monitors" was enabled. Even though the option is disabled in the client.
- The connection only works correctly if "DPI aware" is disabled in the Parallels Client
- The problem occurs with both the latest and older Parallels Client versions (same behavior).

My assumption:
I do not think the client is the root cause, but rather the RAS server component or the RDSH Agent.
Unfortunately, we cannot fully verify this without setting up a new RAS environment with an older version, which would be very time-consuming.
Current version in use: RAS 20.2.2
According to the customer, the issue only started appearing after switching to Windows 11.

Question:
Has anyone experienced similar behavior? Could this be a bug in the RAS Agent?
Is there any known workaround other than disabling "DPI aware" in the client?

Thanks in advance!
Patrick