I’d say it depends. Some people don’t care about certificates or what kit it is and just want a pretty reborn.
If you want to resell the blank kit, it will probably make it less valuable.
How frustrating! So sorry. I have only had one customer who has asked if her baby would come with a COA. But I only sell B.B. not sure how people feel about other sculpts…
I would tape it together to prove who the kit is, because of all the fake knock offs… I wouldn’t care what condition the COA is it (things happen) but JMO, would not buy a kit if the seller didn’t have it. seems like everyday the scammers copy another kit at least you have the proof, even if it is in bad condition