After a few more hours of rigorous debugging, the error was as expected, something very silly. I must thank jhourcle for sort of pointing it out. Setting on_fault to sub {} does cause the program to ignore all sorts of errors be it transmission or message related. My SOAP call was as follows:

 $result = $soap->call(SOAP::Data->name('LoadIntraDaySwap')->attr({
+xmlns => 'https://www.primebroker.com/'}) => $elem );
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In the event of a transmission error, $result would be set to undef. A statement in my code somewhere down the line said something like

print $result->fault();
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Now I am trying to call an function for an undefined item. This caused the program to crash. Thanks again everyone for all your help.