Hi,
very good question indeed.
Since you're an IT guy, it should not be a big problem for you writing a couple of VBA code lines.
Your starting point would be the DataRecordsets and DataRecordset objects.
(
https://docs.microsoft.com/en-us/office/vba/api/visio.datarecordset and
https://docs.microsoft.com/en-us/office/vba/api/visio.datarecordsets )
The easiest would have been to edit directly the document property of the datarecordset object, but alas, it is read only.
So you'll probably need to delete the original and create a new one, re-establish the connections ,... etc.
(A very bold idea: why not target directly the document name of the excel workbook in the XML file of the Visio drawing? Not sure if it could work. but then you wouldn't need to rewire everything)
As link for the new excel file, you could either use the name of your visio file and probably require the file to be in the same folder,
or you have your macro ask for the location of the new excel file.
Also bold, packing the visio and the excel file in a zip and hoping they could communicate by means of relative paths alone. Not sure if that could work.
By the way, using a proper identifying system (unique IDs) you can wire shapes automatically to a dataset.
So far for my 2 cents,
Looking forward to what you come up with.
HTH,
Y.