Was Guth inflation propelled by what we now call "Dark Energy"?
One flaw is saying that the big bang occurred at a location. It didn't: the whole universe was once part of the big bang. So the stuff about deceleration being seen as acceleration isn't true.

Secondly, shortly after the big bang, the universe behaves "ballistically" (although following the rules of General Relativity, not Newtonian gravity). It was initially decelerating and the influence of dark energy was negligible.

But in the popular $\Lambda$CDM model (the prevailing model at the moment), the dark energy density is constant, so as the universe gets bigger it becomes more influential and the universe began to accelerate a few billion years ago.

None of this has much to do with inflation, which, if it happened, happened in the first tiny fraction of a second, when the universe was dominated by some energy density, similar in effect to dark energy (in that makes space expand), but much, much stronger. Exactly what this energy density was is still speculative, and inflation remains a "bolt-on" to the big bang model to explain why space is flat and why different parts of the universe appear very similar.