No need for the extra block:

use List::Util shuffle;
        @weighteddiv  = shuffle @weighteddiv;
        @selected = ();
        xyz: foreach $i (0..$maxclients-1) {
            if ($#weighteddiv > = 0) {
                $idx=int(rand($#weighteddiv));
                $selected[$i] = $weighteddiv[$idx];
                if ($i>0) {
                    foreach $j (0..$i-1) {
                        if ($selected[$i] == $selected[$j]) {
                            redo xyz;
                        }
                    }
                }
            }
        }
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