Could you please identify the part of the code where a timeout for regular expressions is not specified and paste it here? This will help me reproduce the problem locally and then fix the issue.
I reviewed your utils.cs and there are no instances where S5332 or S6444 should raise. Then I noticed by looking at the API call response that both issues are marked with "status": "CLOSED". According to our issues page this indicates that the issues were initially raised, but you subsequently pushed a version with the fixes, leading to the closure of the unmatched “base” issues.
That explains also why the lineNumber is null in the report.
You should still be able to view these issues in the UI. I will ask for some help to my colleagues on the SonarQube team who can assist you on this matter