I don't really understand what the Useqq option does for me in this instance?

Without Useqq, the module will output some characters literally, which may cause garbled output and could in theory even cause it to appear that certain log messages weren't being output, e.g. when showing a logfile with cat or tail.

$ perl -MData::Dumper -e 'print Dumper("Hello,\rWorld!")'
World!';'Hello,
$ perl -MData::Dumper -e '$Data::Dumper::Useqq=1; print Dumper("Hello,
+\rWorld!")'
$VAR1 = "Hello,\rWorld!";
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Are you assuming there might be problematic characters in the output causing this unusual behaviour?

Actually, I think those characters are the least likely explanation, but I wanted to have all bases covered. I'd be much more curious about the results of my other suggestions?

... what the Useqq option does for me ... Are you assuming there might be problematic characters in the output ...

Taking the liberty of responding for haukex: I don't think problematic characters are necessarily assumed to be present, but if they're there, Useqq will help you see them. See also Data::Dump.