I don't know why they chose to make qw not interpolate, but just for kicks, you could cause interpolation in qw with something like:

my @option_config = map eval qq("$_"),
                    qw( $UNIQUE_OPT
                        $FORCE_OPT
                        $VERBOSE_OPT
                        $OUTPUT_EXT_OPT=s
                      );
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