That must have been hard to give up, but I hear ya about this being an enjoyable experience for the community. I'm sure if I had 2-3 guesses I could figure out who the owner of them is

Would be awesome to own that set!
also in the card collecting world printing plates dont usually fetch anywhere close to regular 1/1 cards. often times they wont sell for more than 10% off what a regular 1/1 if the same card would do
If these printing plates were to be sold here they would fetch an absolute fortune. These aren't just some random players printing plate, with bitcoin and cryptocurrency blowing up like it has, they are in super high demand. Just take a look at ebay and how much all the cards are selling for. These plates essentially are 1 of 1's, and would fetch just as much and even more than some other 1 of 1's.
Although it would take a special buyer, I still say the rainbow of four #83 plates would have a value of 1 million dollars. Just the impossibility of putting all four together deserves an award.

I don't disclose who owns what as many owners like to remain anonymous. I have had the opportunity to actually hold two of the printing plates. That was pretty cool