When you first encounter the Gooey Shopkeeper, the PC remarks that they are not made of goo, making her merchandise useless to you even if you are, in fact, made of goo. I imagine it simply doesn't check your race or not much thought went into it.
“I’m glad you asked. I sell nothing but the highest quality samples of goo, perfect for patching up nasty scrapes, fixing buildings, lots of other things, and even more stuff!” she says, showing off the softball sized spheres of semisolid gel. The jellied orbs jiggle softly at the minor vibrations of the cave, but don’t fall from the table they occupy. You mention that you aren’t made of goo, so most of those things won’t help you.
Okay, hopefully fixed for the next release. The content actually acknowledges if the character is goo or not in some places, but it is looking for if your character is literally a goo--the kind with 1 amorphous leg. I've broadened the checks for those to include any gooey parts, so maybe that will help.