...
eval { 
  local $SIG{__WARN__} = sub {
    print STDERR "HOOKED __WARN__\n"; 
    print STDERR Carp::longmess();
    return();
  };
  local $SIG{__DIE__} = sub {
    print STDERR "HOOKED __DIE__\n"; 
    print STDERR Carp::longmess();
    exit(1); # or in your case return()
  };
  # Examples - message not printed due to hooks.
  # CORE::warn("Warn Message:\n", @_, "\n");
  # CORE::die("Died Message:\n", @_, "\n");
  $DT = DateTime->new( year => $year, time_zone => $tz ); 
};
return if $@;
...