Your client probably did this inadvertently by using the 'safe saving' of the Document Inspector. You can explore this by going to File > Options > Trust Center > Trust Center Settings > Privacy Options > Document Inspector > Custom XML Data.

I would expect that by putting the file back into Sharepoint you have reinserted the xml file which but at that time the fields are empty by default so the CCs then go back to showing the field contents again of the text they were previously displaying.

You could create a macro to harvest the contents of each CC and what their xpath mapping is. That might enable you to recreate the xml file in its entirety. I find this pretty complex to code so it would be easier to harvest the info in the CCs and then, after you have reinserted the xml by putting the file into Sharepoint, refilling the CCs with your harvested values to repopulate the xml indirectly.

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Andrew Lockton
Chrysalis Design, Melbourne Australia