特定のタグが無いAWSリソースを探したい

$targetResource = @('ec2','rds')
$results = New-Object System.Collections.ArrayList

$targetResource | ForEach-Object {
    $resouces = aws resourcegroupstaggingapi get-resources --resource-type-filter $_
    $resouces = $resouces | ConvertFrom-Json
    $resouces.ResourceTagMappingList | ForEach-Object {
        $tagCheck = $false
        $_.Tags | ForEach-Object {
            if($_.Key -eq "CostDivision") {
                $tagCheck = $true
            }
        }
        if($tagCheck -eq $false) {
            $result = New-Object psobject | Select-Object ResourceARN , Tags
            $result.ResourceARN = $_.ResourceARN
            $result.Tags = $_.Tags
            [void]$results.Add($result)
        }
    }
}
$results