@ArshadSafrulla thanks for the details. Based on your input, (although I haven't seen the case notes) I'd say this request is non-standard and not necessary. You clearly stated that all 4 APs are faulty and you have tried multiple tests on each individual AP and there is no status LED of any kind on any of them. You even tried PoE injectors.
I cannot imagine why they might want a photo or video, this seems pretty simple, and if you have 1500 APs deployed, you are well aware of how to diagnose a faulty AP. I don't see what a photo would or video would prove beyond the info you provided.
I would call into the Enterprise Support hotline for your area https://meraki.cisco.com/support/ and select option 1 for an existing case and when the next available NSE picks up the call it might be best to re-explain this on a live call and ask them to process the RMA.
It's possible since you might have a single case to RMA all 4 APs, they may have a different protocol for "bulk RMAs" which might have prompted the request, not sure. And if that's the case, you certainly have the option to take a few minutes to open a case for each failed AP, but I wouldn't think that should be necessary. Will have to speak with your NSE. And if there is still pushback, engage with your local Meraki sales team to assist. Good luck.