Many people use these types of glues in reef tanks for frags and such, although I generally would not try to use it underwater because it may not work that way.
ethyl cyanoacrylate is just fine to use....and actually needs moisture (water) to cure properly. It is the "common" cyanacrylate in Krazy Glue, Super Glue and many other "one drop" glues. I see no problem in using it. If it makes you feel more comfortable, it's an acrylic resin....similar to Plexiglass.
I think you may be misunderstanding the chemistry. "Cyanoacrylate" is not a chemical, at least not one in adhesives.
The two ingredients in your product are ethylcyanoacrylate and an inhibitor to keep it from hardening in the tube. People often refer to this type of adhesive as a cyanoacrylate, and sometimes they may contain other varieties of monomer, such as methylcyanoacrylate.
Again, you are misunderstanding the chemical names.
There is no cyanoacetate in an adhesive. There is no individual chemical called cyanoacrylate that is in an adhesive. "Cyanoacrylate" is a laymans term for a family of chemicals, of which ethyl cyanoacetate is the one in the glues.
But this new one I got says that it is not recommended for bonding parts which are subject to great shock or immersion in water. So will this one work?