Hello @ABinkowskiATDOCOsoft,
I have been doing more investigation on this issue.
It seems that in the particular case of S1144 (and S4487), it does not work. The severity is ignored for some reason.
This seems to be only the case when invoking our analyzer with SonarScanner for .NET.
I have created a ticket in our backlog to fix it:
https://sonarsource.atlassian.net/browse/SCAN4NET-16
Have a great day!