Are there other possibilities? The idea of "conditions" may also be considered separate from the origin event. (Like bringing two people together before they can fall in love) Such conditions assume the cooperation of homogeneous and heterogeneous causes
Really? which is Which, and why?
In one scenario, the logical conclusion is that principles of life always existed because the characteristics of biotic life are caused by prebiotic life. The causes are homogeneous and the nomenclature of life/nonlife is merely practical. (Even in a world consisting exclusively of uniform homogeneous natural causes there is differentiation; everything is not everything). This view suggests that a laboratory in the future will generate life from nonliving matter, or that such an even will be discovered outside of the laboratory. We can say that the transition from nonlife to life is not time-specific and has unrestrictive application. Life is a function of nonlife. This leads to a very difficult problem: why does the fossil record suggest a beginning which suggests that life had an absolute beginning. The easy answer is, because conditions were not favorable. I think this question pushes the search in a new direction.
If this scenario is rejected because matter does not hold the causative agent for generating living matter, that means there is a heterogeneous causative agent which would at least have to be immaterial.
I think we'd probably need to clarify our definitions likewise. You seem to imagine a kind of breath of life that is needed for life to exist. I would say that this isn't a separate force or quality, but that "life" is an emergent property from complex chemical systems. So I suppose that would fall under your definition of "homogeneity," although I'm not sure why you use that term. However, I doubt we'll ever be cooking up new life forms based upon different chemical systems in the lab just because the number of possible routes that need to be sampled are so humongous that this could not be done in a reasonable time span. I can definitely imagine that we will eventually be inventing new genes to produce new enzymes with novel functions, although I doubt we'll ever have any "from scratch" custom organisms larger than unicellular.