Narrow backless booster?

I'm so out of the car seat world. DD is 7 and DS3 is 10. Neither quite meet the 5 step test in our new car (woot!!) and we need narrow backless boosters that are good for "puzzling". We have a 2012 Honda CRV and honestly the layout looks pretty good for car seats! The seat is nice and flat and divided. I'd love to find 2 narrow backless boosters that puzzle well and allow for someone (probably DS2 or me) to fit in between the two boosters.

I saw these on Amazon but I don't know if they're as narrow as they perhaps look? They're fairly highly rated.

https://www.amazon.com/Diono-Backles...0&rdc=1&sr=8-5

Would love your advice!