Yellow-banded Thynnin Wasp

Size about 18mm. A huge ant with some prey mistook me for a tree. When I swished it off me, I could not find it on the ground. Instead, there was some earwig-like creature roaming the grass. It moved fast, but very deliberate, almost predictable. And soon, it was clear that it must be a wasp looking for prey. It moved away from me, but only hopped from grass to grass, literally undercover. I took plenty of photos whenever it emerged. Actually, I am quite proud that one pretty good photo is uncropped. Taxonomically, this is not easy to identify without reference books (which I don't own). The fact, that I could not find a 100% match, is an indication to me, that it might not be well documented. Unfortunately, this is a taxon where someone in authority messed up more than it fixed. Actually, I assume that happend more than once and with different cleaning-up job in mind since the mess is incomprehensible and not easy to be resolved. GBIF and ALA are not in line, have lots of missing synonyms, don't show taxa which they themselves mention. Actually, I had to peak into the US bugguide.net to get some better understanding. Could it be an unknown species? Absolutely not! I am an absolute beginner and found this wasp in a well-frequented public place. Also, it is way too big to go unnoticed over centuries. It could be an endemic though. I matched the species to a Catocheilus specimen identified on Bowerbird. It shows exactly the same body form, and thorax pattern and colouration. Abdomen colour differs slightly.