But that simile is about a Tathagata and I don’t think it is the pertinent simile in that sutta is it? Instead the key simile here is a burning fire. The Buddha is saying something quite different from what you suggest here I think. Or maybe you are suggesting that an ‘extinguished fire’ lies deep within a ‘burning fire’? That seems quite strange to me, but maybe that’s a valid interpretation?
I’ll just expand that quote that you have given a little bit…
What do you think, Vaccha? Suppose a fire was burning in front of you. Would you know: ‘This fire is burning in front of me’?”
“Yes, I would, Master Gotama.”
“But Vaccha, suppose they were to ask you: ‘This fire burning in front of you: what does it depend on to burn?’ How would you answer?”
“I would answer like this: ‘This fire burning in front of me burns in dependence on grass and logs as fuel.’”
“Suppose that fire burning in front of you was extinguished. Would you know: ‘This fire in front of me is extinguished’?”
“Yes, I would, Master Gotama.”
“But Vaccha, suppose they were to ask you: ‘This fire in front of you that is extinguished: in what direction did it go—east, south, west, or north?’ How would you answer?”
“It doesn’t apply, Master Gotama. The fire depended on grass and logs as fuel. When that runs out, and no more fuel is added, the fire is reckoned to have become extinguished due to lack of fuel.”
“In the same way, Vaccha, any form by which a Realized One might be described has been cut off at the root, made like a palm stump, obliterated, and unable to arise in the future. A Realized One is freed from reckoning in terms of form. They’re deep, immeasurable, and hard to fathom, like the ocean. ‘They’re reborn’, ‘they’re not reborn’, ‘they’re both reborn and not reborn’, ‘they’re neither reborn nor not reborn’—none of these apply.