Nothing I buy ever fits. That is why I have a drawer full of stuff that will work to make things fit. Like, when I got my eBike kit, the battery took up all the space for both water bottle mounts. On a lark I bought another tire pump, a cheapo Bell. Well, the pump was worthless but I found out the mount that came with it would hold my good pump, off to the side. Yeah!
The console didn't fit with the hardware they sent along with the kit. I had to whip out my Dremel tool and carve out some mohagany making my own mount for that. Something else didn't fit my handlebar either. I looked in my drawer of crap and found a rubber sleeve that took up the 3mm of slack. I could have used an old popped tire tube too, but let's get riding!
Wait, my throttle is a solid ring with a tightening band inside. I had to take the handle grip off to slide it onto the bar from the end. Your problem sucks. See ya, wouldn't want to be ya!