SELinux by its very nature can block many features of rsyslog (or any other process, of course), even when run under root. Actually, this is what it is supposed to do, so there is nothing bad about it.
If you suspect that some issues stems back to SELinux configuration, do the following:
If it now succeeds, you know that you have a SELinux policy issue. The solution here is not to keep SELinux disabled. Instead do:
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