@Anonymous Apologies for the delay in response and all the inconvenience caused because of the issue.
I did some research and had internal discussion as well on same. Currently there is no Powershell command to actually tell you whether the image has been reimaged or not. You can check same on portal You can only see it in Activity Log of that VMSS Next to corresponding Resolved Logs says which instance is re imaged, Adding the screenshot for the same:
Hope it helps!!!
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