Do you mean Wikipedia, or some other wiki? FWIW, the Wikipedia article on Big Bang credits Lemaître for BBT, and Gamov for big bang nucleosynthesis. I do not know the details of "the primordial atom" model, but it sounds like he had the general principles of BBT. Modern BBT models are surely different from his, but modern evolutionary biology is a lot different from Darwin, and yet Darwin is still rightly credited as the father of evolutionary theory, even though many others also contributed to the modern synthesis.

But Wikipedia also says that Hubble's Law was formulated in 1929, only two years after Lemaître, not "decades".

Take it for what it's worth; Wikipedia is fine for a starting point, but it's not the most authoritative source. Really, quoting Wikipedia to support a position does not look good; it's like saying, I don't know what I'm talking about, but I spent 30 seconds researching it. (I use it a lot, myself, but not when I need a debate reference.)