Array_filter vs foreach/loop

updateWinnerBalances.php

$matchU = array_values(array_column($winners, 'userID'));
$matchAmT = array_values(array_column($winners, 'amount'));
$count = count($matchU);

/* Method 1: for loop + foreach (identical result, preserves keys =[ )*/
  for ($n = 0; $n < $count; ++$n){
    if ($winners[$n]['userID'] === $matchU[$n]){

        $new[$matchU[$n]][$n] = array($matchAmT[$n]);
    }

  foreach ($winners as $key => $val){
    foreach ($val as $k => $v){
   if($k === 'userID' && $v === $matchU[$n]){
        $matches[$v][$n] = array($matchAmT[$n]);
        
            }
        }
    }
/* Method 2:  Array Filter, oddly if I remove array_values from Filter it preserves keys too but fiddling with that on method 1 doesnt result in diff outcomes */
    
    $winnerz[$n] = array_values(array_filter($winners, function($var) use ($yday, $matchU, $n) {
    return ($var['start'] == $yday && $var['userID'] === $matchU[$n]);

}));

    /*
RETURNS
Method 1: for loop + foreach (identical)

Array
(
    [11d127b492bb] => Array
        (
            [0] => Array
                (
                    [0] => 28
                )

            [2] => Array
                (
                    [0] => 74.454545454545
                )

        )

    [bataboom] => Array
        (
            [1] => Array
                (
                    [0] => 78.272727272727
                )

        )

)

Method 2: array_filter

[0] => Array
        (
            [0] => Array
                (
                    [amount] => 28
                    [userID] => user-2
                )

            [1] => Array
                (
                    [amount] => 74
                    [userID] => user-2

                )

        )

    [1] => Array
        (
            [0] => Array
                (
                    [amount] => 78
                    [userID] => user-1
                )

        )
        Method two ftw.. 
    //finish chk balance from uid add up the sumzz and update
        */


$total[] = array_column($winnerz[$n], 'amount');
$uid[$n] = array_unique(array_column($winnerz[$n], 'userID'));
$sumz[] = array_sum($total[$n]);
$fb[] = $uid[$n][0];
$bal[$fb[$n]] = fetchBalance("$fb[$n]");

$updateBal[] = $sumz[$n] + $bal[$fb[$n]];
$userKeyz = array_keys($bal);
updateBalance("$userKeyz[$n]", "$updateBal[$n]");


}