It does indeed look like a Physalis sp. FataMorgana

One of the native Lespedeza.

I suspect either a squirrel or raccoon tore the screen and then the black snake took advantage of it. Squirrels are known to tear through screens, although I don't know what they would be after in your courtyard. Raccoons would be attracted to the water and certainly the fish and could easily tear through it. The snake is probably after the lizards and maybe even the fish if they are small. What makes you think it's nocturnal? Squirrels aren't night feeders but do move around in their nesting places at night, have you found any nesting material? Raccoons and snakes do hunt at night.

If liriope would thrive in your planting zone, you might consider outlining your side and front yards alongside all concrete/cement with that. Now that you can see what is there, you can better decide what you do like and what you don't. Get some kind of stakes or sticks -- anything tall enough -- and some light colored surveyor's ribbon and "rope off" what you intend to keep. Take pictures. Now you can stop by local landscaping businesses and have a two way conversation. One idea: After you do that, contact a local landscaping business and tell them you intend to remove everything from your yard by (a date certain) EXCEPT (what you want to keep -- hand them a written note and photos and/or diagram for clarity) and ask them if they want any of it before you "plow it under". Be clear you're not offering to pay them to remove it and you don't want a bunch of deep holes left in your yard -- let them know that you're just offering what you don't want "free -- that they can have it if they remove it (by a date certain with you there at the time). Make sure you want to be there when it is removed to be sure they don't remove anything you want to keep.