If this was a case of tampering, and I think it is, there is a scenario where the label doesn't have to be removed. The consignor has two slabs, one is an 8.0 and the other is a 5.0 (the problem book). He gently removes the inner well of the 8.0, leaving the label intact. He deslabs the 5.0 but leaves it in the inner well. He then places the 5.0 into the 8.0 slab. You now have an 8.0 slab, label intact and never touched, with a 5.0 book in the inner well. Trust me, you can crack open a slab and remove the inner well with minimal evidence of tampering. I think CGC will find that the hairline crack an inch below the top corner is the evidence.