Hello there TripleGemStudent,
(I got it right this time!)
Here is my contribution:
I too had read something about “one of Buddha’s former lives when he was in hell”.
And also, if I remember correctly, it was only for a very short span of time. But I am not sure here whether that was about a Chief Disciple rather.
However, the perplexity arises from the use of the word ‘Buddha’.
If taken in the sense of ‘the one WHO HAS SINCE become a Buddha’ the notion is not at all startling. That is, before he even set out on the path to become a bodhisatta, before all that he had been just a normal being drifting in sansara from a time without beginning, just like the rest of the beings. And the records in the nama gotta are not limited to the past 91 mahakappa. They go back infinitely into the past. Just as he had been a Boddhisatta before becoming a Buddha, He had been a normal being in sansara before that. But we keep referring to Him as the Buddha in all circumstances, because that is what he finally achieved. Like when we say: the Professor was a student at so-and-so College (Now he is no longer a student at that college)
It is said that the time it took Him to fulfil the paramita (the requirements) spanned the time of 512,000 Buddhas. Taking the number of Buddhas in the last 91 mahakappa, 8, with the estimated duration of a mahakappa ( 80 billion years) as an average, we get : 91/8 x 512,000 x 80×10^9 . Close to 5×10^17 years. Insignificant compared to the all the infinite time before.
So there is no reason why a normal (until that time) being in sansara, including those later to become Boddhisattas and Buddhas, should be exempt from the hells. It is actually impossible, seeing that, until the attainments, most births are in the apaya.