Any other way to check - I have a few more shots with different angles

paper wasps don't really have seperate "queens"... simply reproductive females and in mostly all species, there is no way to tell a "queen" from a worker. however, in dominula, the more dominant the wasp the more black it has on it's face. toward the end of the season when larger workers emerge, they too will have some black on their face so telling a queen at that point is hard. but right now any workers out will be small and not have black on their face

I didn't know about the dots, thanks for the hint. Also this time of year the 'queen' is usually still making the nest.

although just because it does not have dots on it's face does not mean its not a queen. i have seen some queens (with nests before workers emerged) with no black on their face at all. some queens have it, some dont but most dominant wasps of this species do

I looked through some of my last year's photos and noticed that some had and some didn't. A 'queen' is simply a fertile female as opposed to a sterile worker, so there would naturally be a mix towards the end of the season, wouldn't you think.