Help sending Get-Eventlog output to an output textbox

I have a powershell app I'm working on.  One of my buttons is called GPUPDATE Verify where it calls a function to check the system log on a remote system to make sure GPUPDATE ran on it and send output to a textbox.

Below are codes.  Can't figure out why it is not displaying the results into the textbox.

I'm still new to all this so please be gentle!  lol

#OUtput Box

$OutputTxtbx = New-Object System.Windows.Forms.Textbox
$OutputTxtbx.Location = '335,200'
$OutputTxtbx.Size = '200,280'
$outputTxtbx.MultiLine = $True
$outputTxtbx.BackColor = "Black"
$outputTxtbx.foreColor = "White"  
$outputTxtbx.Borderstyle = "none"  
$objForm.Controls.Add($OutputTxtbx)
$objForm.Topmost = $True
$objForm.add_Shown({$objForm.Activate()})
[void] $objForm.ShowDialog()

#GPUPDATE Verify

$GPVButton = New-Object System.Windows.Forms.Button
$GPVButton.Location = '110,150'
$GPVButton.Size = '100,23'
$GPVButton.Text = "Gpupdate Verify"
$GPVButton.Add_Click({Verify})
$objForm.Controls.Add($GPVButton)

Function Verify{
        {
        $GPVButton.Add_Click({$GPV = Get-EventLog -ComputerName $WS -LogName System -InstanceId 1502 -Newest 1})
        #$GPV = Get-EventLog -ComputerName $WS -LogName System -InstanceId 1502 -Newest 1
        $GPTIME = $GPV.TimeGenerated
        $OutputTxtbx.text = $GPTIME
                   }
    }