VBA help Opening and closing Excel with in Powerpoint

I am sorry this is so wordy.

I have been working on a Visual Management Kiosk presentation for use on the plant floor to visuallize component replacements of tools for quicker reaction by engineers.

I am NEARLY there with having this Powerpoint behave the way I want it too

I have a couple questions about the code because Google is not giving me answers i need

below is my code. it works, i just need to understand it more to see if I am using the correct settings.
alot of this is mash up of code references and google research

My first question is where i have the Directory of the excel file i want to open: what are ,True,False associated with? what part of the file opening process is it manipulating?

If i set xlApp.Visible=False how do i gain confidence the links are actually updating? is excel actually opening in the background or does this just cancel out the whole thing?

The only reason i am Opening the workbook in the first place was to avoid the pop up to "update, dont update, cancel" pop up that power point would ask every time the updatelinks macro ran.

Ultimate goal is:
Every time the presentation returns to the starting slide then i want it to update links.
i want no pop ups to happen when this occurs. thats the goal.

my 1st itteration
Slide show begins
Links update
Pop up happens, freezes presentation

2nd itteration
Slide show begins
Excel opens (read only)
Links update, No pop up
Excel closes, asks for file save, presentation doesnt freeze but in theory excel will eventually try and reopen and then you cant have 2 files open. so link updating wont happen

3rd Itteration (below)
Slide show begins
Excel opens (read only) (Visibly)
Links update, No pop up
Excel closes, No pop up

Code:

---

Sub OnSlideShowPageChange(ByVal SSW As SlideShowWindow)
    'Trigger Macro to run at starting slide
    If SSW.View.CurrentShowPosition = _
        SSW.Presentation.SlideShowSettings.StartingSlide Then
        'The macro i want to run
        Updatelinks
    End If
End Sub




Sub Updatelinks()
    'Make declarations
    Dim xlApp As Object
    Dim xlWorkBook As Object
    Dim osld As Slide
    Dim oshp As Shape
    'Open source workbook
    Set xlApp = New Excel.Application
    xlApp.Visible = True
    Set xlWorkBook = xlApp.Workbooks.Open("I:\'Redacted intentionally'\Core pin map Calculations.xlsx", True, False)
   
    'look for linked OLE objects in all slides
For Each osld In ActivePresentation.Slides
      For Each oshp In osld.Shapes
            If oshp.Type = msoLinkedOLEObject Then
            'Update the link if it is
                oshp.LinkFormat.Update
            End If
        'Loop
        Next oshp
      Next osld
   
    xlWorkBook.Close SaveChanges:=False
    xlApp.Quit
 
  End Sub

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