You really like to create a lot of work for yourself.
What I did....
I tried the gorilla glue. Dont bother as it is hard to get in and cant really bond to the Luran. The area I did has debonded some a few years later.
What does work is to use 5200 and drill a hole you can put the tip into. With a very strong high quality cault gun you can inject some into the void. With a finger over the hole you pump the area and will get the 5200 to spread about 6" diameter from the 1/4" hole I drilled. Then I put tape and something heavy to cover the hole.
The 5200 is rubbery when cured so it can move. It can stick fairly well to the Luran. Plus I ended up peeling up the non-skid and most of the holes were covered after I was done.
Of course, 3 years later it now the deck is still holding solid where I did the 5200.
I decided my path after doing some experiments. I have some scrap lexan (a close relative to luran) and put some gorilla glue on the surface and put another piece of luran on top. As expected it just popped apart with minimal glue sticking to the surface of one piece. Also the gorilla glue gets stiff and crunchy so flexing and temp variation will stress the bondo causing it to debond over time.
The 5200, well it did not want to let go.
You can spend many hours doing stuff to your boat. I like quick and effective for a long time. What I have seems to fit the bill.