Well unfortunately
Dracaena sanderiana is defiantly not an aquatic plant, I had some in my planted tank growing with it's leaves out of the water ('lucky bamboo', the stem was in the water but the leaves were above), however I moved it when I put my plec in there because I was scared he would eat it. It is now growing well on my windowsill.
Heres a link that says it is toxic to cats and dogs, but I don't know about fish. I remember reading somewhere that you shouldent put it in terrariums with lizards like bearded dragons because it can poison them too, but that was ages ago and now I cant find a reference.
I was just thinking because flying foxes can bite down on things while otos cant.
It may not effect fish, but its possibly worth checking the leaves for possible bite marks.
BTW, in the second pic the grass like plant to the left also looks non-aquatic. I cant see it properly, but it looks a lot like a non-aquatic plant the lfs I work at sells. Mainly to people who want something the fish wont eat or to people with Aqua-Terrarium's. That ones not poisonous to fish though, I've seen a silver dollar eat it with no problems. But when kept submerged the tips go brown, algae grows on the plant and it slowly dies. It's
Acorus sp. I think.