I just want to double check before I do anything... because the instructions are species specific I don't have to worry about having my pet as the same species before hand, yeah? And it won't matter if it's an experiment either?

I had a Nostalgic Swampie that was made from a Galactic Fester. The instructions in the stickied thread Frequently Asked Questions & Answers in this forum only say that the pet has to be existing, and nothing else about its species. Since Experiment is a species (that they weren't intending to plush/bag for collections and paint over in the standard colorfills) they should work.

[edit] many of the Mahar Elixirs sell for cheap in Pawn. Consider it an extra safety measure or just an additional quest ingredient and turn your Experiment into a regular pet with one?