I think you're a little lost. Everyone who has the Redstone block medal, (401+) all their medals after that would need to be changed. That is quite a lot more than 10 people. I had no idea this was possible.
My apologies, I thought he meant the enchanting table would be replaced by the slime block, not just the total removal of the enchanting table and Redstone Block. Now, this suggestion makes a lot less sense logistically because there is only two people to do hundreds of medals. Unless you change it to where the slime block replaces the enchanting table as a whole, and keep the redstone block, I don't think this will pass through. -1
I'm pretty sure that all they have to do is change the "Features $401-$500" medal and above's image but once again, I'm not sure.
Not sure what you read, but I never suggested to take away the redstone block. Just renaming the medals and changing the icons is all that's needed. Essentially it would just add the slime block before the redstone block and move the list up, removing the enchanting table to still make the command block the last one (by my request.)
Each medal that moves up the line would need to be changed/renamed individually but it would affect everyone that has those medals simultaneously.