OK..... Did you try my idea? This is a proven way of recovering items on the bottom. (when you own a boat, you get creative)
I know all about being creative I haven't had much time, but will look at the idea Drone or Boat. Unfortunately without access to a boat that fits into schedules, family things coming up & the weird weather around here lately just haven't had much time to devote to the retrieval. I did try a little 'probing' of the bottom with a PVC pipe of about 10 ft with a wading net attached but that wasn't a fun experience, all that I really ended up with was pulling up a lot of nasty silty mud. I'm going to go ahead and see about fabricating that little device, it won't hurt anything. I've also got a friend as soon as this flu that's floating around the house clears that's SCUBA certified & we are planning to head on out there with a metal detector to see if we have any luck. As our lake is really still young, it's challenging because of all the silt on the bottom (even in the older section where it went down) & the clarity of the water is awful.
I'm keep everyone updated through when the refresh expires though. Success or no success.