Actually, I discovered the "poorly painted" mount previously. I had an arrow in my picture pointing to it... looks like it was done with a sharpie. The point is - the colour is not "close" or near enough, it is...
Identical.
Cutting out material and gluing it down to some wood isn't that complicated either IMHO. They did it with 20 other Hero boards, didn't they? And with all due respect, the quality of the photos isn't good enough to judge whether the hole pattern has depth or not. It could very well have some depth.
We've seen the prop makers ability to match the colour of the boards to the decals and it stinks... you never know, maybe this wasn't intended as a "Stunt" board. They probably made it a Hero for the possibility that it might be visible on screen.
The production crew of the Back to the Future films are well known to be overly detailed and thorough in their approach. They were most certainly not simplistic...
In the case of the orange board they even made sure to change the text of "Hover Board" (just so it "goes" with orange) to blue and added Velcro strips. If they had known how much of the board would be seen they wouldn't have made little more than a wooden deck painted orange... It was made with all of the details for a reason. It only makes sense that there would be a rubbery material like on the pink board.
And sure, obviously they were well equipped in making vinyl decals. They probably had the Universal sign shop at their disposal. All of the boards in some way or another are made up utilizing some sort of vinyl decal, whether it's a few details, a full board decal, or a small Pitbull logo. That doesn't change the fact that there were boards that had hand-applied lenticular material on them that was separate to the vinyl.