Opening Read-Only from Sharepoint causes "Save As" prompt

I have a workbook that is saved to a Sharepoint site. When the workbook opens, it runs the following code:

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Anyone who falls under the "Case Else" portion of this, still gets prompted to save the file (in which they CAN override the original).

With our environment, the following solutions cannot work:
1) I cannot have them open another workbook and then from there open this workbook.
2) I cannot mark the directory they open this from as Read-Only
3) I cannot mark the file itself as read-only.
4) Read-Only recommended can still be bypassed.

Is there ANYWAY that this can be opened from within the original document as read-only without any prompts to save for the people that it changes to read-only for?

This seems to be just what was missing. Thank you!