My solution already does exactly that. Just replace the body of if ($@) with whatever you want.

What you have there is the same as

eval ("use fakemodule;");
if ($@) {
   print "error happened $@";
} else {
   print "error didnt happen, do some stuff";
}

print "Content-type: text/html\n\n";
print "here we go again...";

&a;

sub a {}
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