Wow that’s fascinating! Also your advice that it is a landslide area solves the mystery why all that rock looks quite fresh yet the munitions are obviously quite old. Maybe the BlueROV2 is a better option for cleaning up this area as it is quite deep to dive (and cold!).
Will check your channel as I’m only a newbie in this field and keen to develop commercial applications for ROVs. The BlueRobotics ROV provides an excellent development platform and high quality components. See my first ‘Dive Log’ on this forum ( ROV Rescue Pittwater, NSW Australia. Its a bit long and amateurish but we all gotta start somewhere!