Refresh a variable within a foreach statement

Question

We have a master registry within our on premise SharePoint environment, to keep this list accurate, we run a clean up script each day to remove the item within the list registry.

As part of this script, we wish to delete the AD permissions group at the same time.

Our script works when deleting a single site collection, but when multiple are deleted, the script removes the list item, but attempts to delete the same AD group over and over, it doesnt refresh the variables.

Here is part of the script:

Add-PSSnapin *sharepoint* -ErrorAction SilentlyContinue
Import-Module ActiveDirectory

#Adding variables
$siteRequestUrl = "https://contorso/sites/demo"
$siteRequestListTitle = "Registry"
$webAppArray = @()
$listSCArray = @()
$itemsToDeleteArray = @()
$dn = Get-ADDoman | select -ExpandProperty DistinguishedName
$ou = Get-ADOrganizationalUnit ('Ou=SharePoint, OU=Account Groups, OU=Groups,' + $dn)
$ouSDL = Get-ADOrganizationalUnit ('Ou=SharePoint, OU=Resource Groups, OU=Groups,' + $dn)

Start-SPAssignment -Global
$list = (Get-SPSite -Identity $siteRequestUrl).RootWeb.Lists | Where-Object { $_.Title -eq $siteRequestListTitle }
$expectedSCCount = $list.ItemCount
$WebAppSCCount = $list.ParentWeb.Site.WebApplication.Sites

If ($expectedSCCount -ne $webAppSCCount) {
    $listItems = $list.Items

    foreach ($webAppSC in $list.ParentWeb.Site.WebApplication.Sites) {
        $webAppSCArray += $webAppSC.Url
    }

    foreach ($item in $listItems) {
        $li = New-Object Microsoft.SharePoint.SPFieldUrlValue($item["URL_Link"])
        $listSCArray += $i.Url.String()
    }

    $comparison = Compare-Object -ReferenceObject $webAppSCArray -DifferenceObject $listSCArray | where-Object -FilterScript { $_.SiteIndicator -eq '=>' }
    foreach ($difference in $comparison) {
        foreach ($item in $listItems) {

            $i = New-Object Microsoft.SharePoint.SPFieldUrlValue($item["URL_Link"])

            If ($i.Url -eq $difference.InputObject) {
                $itemsToDeleteArray = + $item
            }
        }
    }
    $itemTitle - $itemToDelete.Title.ToString()
    $itemTemplate - $itemToDelete["Template"].ToString()

    ######  Now I move onto the problem, these variables work but do not not refresh if more than one item is being deleted ############

    foreach ($itemToDelete in $itemToDeleteArray) {
        switch ($itemTemplate) {
            "Branch1" {
                $managedPath = "BR1"
            }
            "Branch2" {
                $managedPath = "BR2"
            }
        }
        $forceLowerCase = $itemTitle.ToLower()
        $siteTitle = $forceLowerCase -replace '\W', '-'
        $GroupName = $managedPath + "-" + $siteTitle

        $SggGroupName = "SGG_" + $GroupName + "_Members"
        $SdlGroupName = "SDL_" + $GroupName + "_Members"

        Try {
            Get-ADGroup -Filter 'GroupCatergory -eq "Security" -and GroupScope -ne "DomainLocal"' -SearchBase "CN=$SggGroupName,OU=SharePoint,OU=Account Groups,OU=Groups,DC=Contorso" | Remove-ADGroup -Confirm:$false

            Get-ADGroup -Filter 'GroupCatergory -eq "Security" -and GroupScope -eq "DomainLocal"' -SearchBase "CN=$SdlGroupName,OU=SharePoint,OU=Resource Groups,OU=Groups,DC=Contorso" | Remove-ADGroup -Confirm:$false

            Write-host "AD Groups $SggGroupName and $SdlGroupName deleted" -ForegroundColor -Green
        }
        Catch { write-host "AD Groups $SggGroupName and $SdlGroupName failed to delete" }

        $itemToDelete.Delete()
    }
}

Stop-SPAssignment -Global