Nfl Carolina s McCaffrey led the league with 91% snaps and over 300 touches. He fumbled 4 times. Only 2 other backs took over 80% of snaps. Barkley(350 touches and zero fum.) and Elliott (400 touches 6 fum.). So, in comparison your back as active as these guys, but doesn't have the same talent. Most notably speed .
Here I would never play a back that much because he'd get injuried or fumble. The only reason I note speed is that here it makes plays and irl possibly these speedy guys avoid big hits or easy strip sacks. Or they smarter and secure the ball late in the game.
Really I would chalk it up to randomness favoring fumbles due to fatigue . Parabolic changes would exponentially expose both. Still, a back in rivals had nearly 400 touches and only 4 fumbles with 97 avoid fumble..
https://rivals.myfootballnow.com/player/3236