Ultimately I ended up using Great Stuff Pond&Stone on aquarium grid, then I pressed the cork bark and preserved moss and other pieces of wood into the foam and let it all set. Then I attached suction cups to the back and placed the entire grid into the tank, which I used with zip ties that I tied onto the back. I have a false bottom also made from aquarium grid, inside the grid I placed filter foam and have a heater/thermometer, a filter and a water pump for a water feature (still working out the kinks). (The last photo on this post shows my grid, the filter foam was placed INSIDE the grid instead of outside as photographed, I was just making sure I cut the right size there)

Plants - syngonium, eripiprenum, philodendron, orchid, scindapsus, begonias, sarracenia, monstera, pinguicula, an air plant, maidenhair fern, anthurium, string of turtles and planted in the water is standard dwarf grass and a Java fern that I got as tissue cultures to avoid the whole bladder snail thing haha. Not pictures but added later was callisia repens (looks like a tiny tradescantia) and selaginella uncinata (a crawling fern that behaves like a moss)

Just felt like sharing, probably will re-do the entire thing because I added the water feature later and stuff started falling off. I need more terrain and soil, or I need to maybe remove some of the soil-liking plants but I've had a lot of luck with propagating and hydroponics, I have new growth on almost everything except the pings, sarracenia and maidenhair fern. They aren't dying but they aren't looking particularly happy. Eventually I'll add some isopods, maybe a couple fancy guppies and still undecided on the primary animal which will be an amphibian or reptile that will thrive the best in the tank I made. This is far in the future because I need to do a lot more research about livestock and safe plants (I have a few that are toxic to animals, maybe more than not lol). This project has been brought to you by OCD and ADHD. Never truly deciding what I want, and never being fully satisfied with what I made hhahahah

Anyway, a work in progress. Happy building fellow paludarians! Stay tuned for the next build.