Or maybe try to ask them how to prepare the device for the warranty claim.

That’s actually a great idea! It’s better to directly confirm this with them than to pointlessly speculate about it.

I could see someone having DVDs from multiple regions, changing drive region every time until they hit the 5 changes limit

This is something new yet interesting to me. Do you have any resources on this? I don’t really know how to search for this on my own.

Unfortunately I’m not from the USA so this option isn’t available for me.