My experience in national parks is the rangers around the park and at the front gate pay absolutely zero attention to ebike classes. When I was at Grand Canyon, the written rule only stated that a) ebikes are allowed on any bike path or automobile road and b) when riding on a path, you have to be pedaling (roads were excluded from the pedaling rule)
And ebikes were literally everywhere. Actually lots of bikes were there and probably 75% of them were ebikes. Many of them rented from two different vendors on-site at the South Rim. You could tell who the analog bike riders were... they were going 2 mph or walking their bikes up the hill on the road to Hermit's Rest. I remember hearing one mom ask her son "how much further?!??" as she grunted up the hill. I was zooming down the other way and didn't have the heart to yell out she was still near the bottom.
So long as you aren't being a butthead, you'll be fine. But in the spirit of the rules and playing well with others... pedal the bike. I have nothing but disdain for Class 1 restrictions but I also ride a bicycle so I can pedal it and rarely use the throttle anyway.
