This community wouldn’t be likely to assist, unfortunately. Your best bet would be to check with Sonos Support directly.

And, frankly, as you’re not purchasing from a verified source, it becomes impossible for someone from Sonos to do any sort of ‘guaranty’, as any data you get from the ‘seller’ could be false, and from a ‘real’ set. It’s really down to how much trust you have in the seller. 

Have you seen fake Sonos ace?

Look to the seller's reputation, lots of fakes and scams out there.

I’ve not ever seen a Sonos fake, ever. I have seen someone who thought they had a Sonos, but it didn’t look like one, nor did it pretend to be a Sonos device. They just made an assumption. 

In general I avoid “new, unopened” merchandise offered by an online individual. There are too many porch pirates selling online and I don’t want to support them. It’s red flag for me if the individual has multiple “new” items for sale. The bottom line is that I don’t have the patience to research the seller.