I have to admit, even as I read your explanations, the concept is a bit hard to follow. Let me try to break it down:
You start off with a word I've never heard of: geopolymer. And Wikipedia isn't much help. I think I have the gist, following Wikipedia and your postings: geopolymer is a type of concrete, made of silicates and other earthy compounds, instead of the carbonates used to make cement since antiquity. And they have specialized properties, thermal properties for example. Cool. You're making artwork out of cement. Lets use that definition from now on, since you're not fireproofing a house, or building a medical implant.
You have a recipe, that gives explicit proportions, but lacking the correct raw material, you made some yourself following another recipe. Before we dive in right at the calculations, we have to remember: either recipe could be wrong. So this may be a futile exercise.
You've quoted some recipes from manufacturers. And you're wondering if there's too much KOH. Here we come smack against a problem of chemistry: not everything exists as a compound. Large, inorganic compound may exist as complex coordination complexes. What I mean to say is, maybe potassium silicate doesn't exist as a compound, but instead, a mixture of silicon dioxide and KOH and we just call it potassium silicate. In which case, we may need more KOH to keep the resulting mixture stable. The manufacturers know this, and so may some materials chemists, but this isn't the first topic in Undergraduate courses.
Of course the best chemical stability may prevent other reactions from happening, for example, cause a failure to set. Did that happen? 'Cause that would be an easier question for a materials chemist or cement making company to answer.
I still don't know the dilemma. You seem to be worried about the KOH in the mixture making the artwork, a set cement, unsafe to touch. That's kinda out there. For example, typical cement contains CaO, lime, which will likewise burn skin. But it sets over time into a solid with long-range organization, internalizing some of the CaO, and I guess, washing off some of the surface. We don't usually worry about touching other set cements.