PowerShell: Check Servers on Domain to Locate A Domain Account Being Set to Run Services and Scheduled Tasks

# Obtain the name of the default domain Administrator account (this account is expected to be disabled)
$domain=(net config workstation) -match 'Workstation domain\s+\S+$' -replace '.+?(\S+)$','$1';
$defaultDomainAdmin="$domain\Administrator"

# Regex key to search for server names: look back to CN= as $0, match anything but a comma as $1, capture CN|OU as $2,separated by =, capture next part as $3
$regexServers="(?<=CN=)(.*?),(OU|CN)=([^,]+)"

# Collect server names and their containers
$servers=dsquery * -Filter "(&(objectCategory=computer)(operatingSystem=*server*))" -limit 1000000| %{[void]($_ -match $regexServers);$matches[1];$matches[3]}|select @{Name="Name";expression={$matches[1]}},@{Name="container";expression={$matches[3]}}|sort-object -Property Name -Unique

Function checkServiceAccount($searchAccount,$sherver){

    # Original function is meant to query multiple machines. It's now adapted to just one machine
    $servers=$sherver
    $runas=$searchAccount
    $scheduledTasksMatch="";
    $servicesMatch="";
    $result="";

    Function Search-ScheduledTasks{
        Param(
	    [array]$ComputerNames = $servers,  #Accepts input and cast it as an array
        [string]$runasUser=$runas
	    )
	    Begin{
            $Results = @() #Initializes an empty array
	        }
	    Process{
    	    If ($_){	#Checks if this function is being called via pipe command. If so, use set $ComputerNames variable as pipe
			    $ComputerNames = $_
		    }
		    ForEach ($Computer in $ComputerNames){
			    If (Test-Connection $Computer -Quiet){    #Checks for connectivity before proceeding
                    # Use the legacy schtasks command from localhost to query remote machine and format an output int CSV format              
                    $tasksAsCSV = schtasks.exe /query /s $Computer /V /FO CSV

                    # Process the CSV result into PowerShell. Filter entries that are not labeled as "TaskName" and by "Run as User" field
                    $result = $tasksAsCSV | ConvertFrom-Csv | Where { $_.TaskName -ne "TaskName" -and $_."Run As User" -eq $runasUser}
                
                    #Appends this result into array collection named results. 
				    $Results += $result 
			    }
		    } #end foreach
	    }
	    End{
            if ($Results){
		        Return $Results."Task To Run"
                }
            else {
                "No Scheduled Events were found for user $runasUser.";
                }
	    }
    } #end Search-ScheduledTasks function
    
    $servicesMatch=(Get-Wmiobject win32_service -ComputerName $sherver | where-object{$_.startname -like $runasUser}|select @{name="ServiceName";expression={$_.name}}).ServiceName|out-string
    $scheduledTasksMatch = Search-ScheduledTasks;

    if($servicesMatch){$result+=("$servicesMatch").Trim()}else{"No services are currently using the $searchAccount."}
    if($scheduledTasksMatch){$result+="`n$scheduledTasksMatch"} 
    return $result;
}

$servers | %{checkServiceAccount $defaultDomainAdmin $_}