Don't get too hung up on it. If you took apart your block you would see its not a big issue due to where the jet plate is. I had a similar niggle with mine with trapped air. Temps where fine though but i managed to get rid of the air pockets and it didn't change my temps at all remained the same.
Also with the 7700k the biggest bottleneck with temps is intel's own thermal interface between the die and IHS. Ive seen custom vs air vs AIO cooler and while custom watercooled remained the best it was not far off AIO and air. Delidding the CPU and using liquid metal or even girzzly kryonaught would vastly improve temps. With my 3770k i dropped 10 degrees on my hottest core with a Corsair H100 AIO with fans at 1200RPM doing a delid with Grizzly Kryonaught and dropped a further 5-7 degrees using Coolabs Liquid ultra.
Also with the 7700k the biggest bottleneck with temps is intel's own thermal interface between the die and IHS. Ive seen custom vs air vs AIO cooler and while custom watercooled remained the best it was not far off AIO and air. Delidding the CPU and using liquid metal or even girzzly kryonaught would vastly improve temps. With my 3770k i dropped 10 degrees on my hottest core with a Corsair H100 AIO with fans at 1200RPM doing a delid with Grizzly Kryonaught and dropped a further 5-7 degrees using Coolabs Liquid ultra.