From a quick look at the code, I would say try replacing line 277 in DBIx/Log4perl/st.pm

    $sth->_dbix_l4p_perl(2,              # line 277
        sub {Data::Dumper->Dump(
            [$res],
            ["fetchrow_hashref($h->{dbh_no}.$sth->{private_DBIx_st_no}
+)"])})
        if ($h->{logmask} & DBIX_L4P_LOG_OUTPUT);
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with

    $sth->_dbix_l4p_debug($h, 2,         # line 277
        ...
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AFAICT, there is no method _dbix_l4p_perl in any of the related packages (while there are similarly named ones like ..._debug, ..._info, etc.).  No guarantees, though (untested).