They did see things that they could not explain. It was kept quiet to avoid causing panic on the ground. Remember when the science fiction radio show “War of the Worlds” aired? What happened as a result? Total chaos. Y’all crack me up. One minute the entire program is a hoax and the next minute we went to space and covered up what we found.
A lot was kept quiet, for interests of national security, there was (in the 50s, 60s and early 70s) defense research being done on these missions. NSA frequently did door to door checks on friends and neighbors who worked in the programs, looking for things that might be odd. Shortly after I moved into my own home I got a knock on the door asking about Charlie Bolden, my neighbor across the street. He was getting ready to pilot a shuttle mission with the Russians. They wanted to know if we had seen anything unusual at their house, strange late night visits, unusual cars that sort of thing. I later mentioned it to my mother and her response was,

Her response was “Oh of course. They used to come around the neighborhood all the time during the moon missions, just making sure there were no spies around” . Lol. As far as the pool, it’s the Sonny Carter training facility used to train for EVAs and constructing the ISS. There is an ISS in the pool with all sorts of tools. Its the only way to train in EVA suits in zero gravity. I can assure you there are no videos being made in that pool without helmets or scuba gear. There are always rescue divers present when there is training underway in case of an accident. With a 2022 budget of 24.6 billion, I’d say we have bugger issues to worry about. Like the Ukraine 150 billion money laundering scheme.