I don't know about that pouch, but I use whatever pouch/purse I want and just toss it between my legs into this thing (minus the tethered pouch) under my chair to carry it. They only seem to come available on Amazon near "back to school" times but they're super useful. Car keys, water bottle, anything anyone hands me I don't want to carry, just toss it under.

https://www.amazon.com/Case-Logic-Under-Seat-Organizer-Wheelchair/dp/B000J0WAKO