Hello @smileBeda ,
thank you for providing the project. I have cloned and analyzed it. The 5 issues you see in the file classes/ class-x-install.php line 219-224 are not false positives. In your case, this rule doesn’t make it so reasonable in this context.
In order not to have the issue reoccur in your case, even if you mark the first issues as "Won’t fix’, you need to disable the rule for this file. This works via the settings General Settings > Analysis Scope > Ignore Issues on Multiple Criteria. Here you can enter the rule php:S1192 and the respective file (in this case classes/class-x-install.php).
For more information on how to customize the analysis, see Narrowing the Focus in the documentation.
I hope I could help you.