Their website just says it is a standard size so should fit any car with isofix points. As a 2015 car yours will have those.
I would recommend asking the shop if you can try it in your vehicle if possible. Angles of rear car seats can vary so much and if the seat is too angled it can cause a poor position for the baby in the car.
Alternatively you could look into getting the car seat adapters for the Stomp which then give you access to a range of branded seats, these are often better than the generic ones for newborn positioning and fitting options.