N0mesora
I’m not sure what you are saying
by definition a davar sheyesh lo matirin will become muttar . Thats literally the defitnion. (Its a machlokes if the heter has to happen automatically, or if a minor act like kashering will also qualify as it will become mutar)
If it won’t become muttar then it is not a Davar sheyesh lo matirin, by definition.
(Even if it will spoil before becoming muttar it isnst a davar sheyesh lo matirin accoridng to Mechaber )
Chometz shevar al hapesach will never become muttar. There is nothing yo ucan do to make it muttar, you cant sell it now cant kasher it is assur forever. IT doesnt matter that could have prevented the issur that is a not a “matirin” . Right now after Pesach is there a way to fix it? NO
Thus it is NOT a davar sheysh lo matirin, and WILL be batul in the proper circumstances.
Of course all other rules of bitul apply, cant be davar shebiminyan, berye, chaticha rui lechichabed, cant intentionally create bittul (ain mevatlin issur lechatchila). Kol kavua etc
The fact that something WAS avoidable doesn’t change anything. Issur neveila WAS avoidable by shechting. nontheless if I intentionally create neveila and it ACCIDENTLY gets mixed up with kosher meat it is batul (again barring the exceptions to bitul mentioned above).
there are a few lines of yours I dont get either. Though I agree the Distributror who didnt sell chometz cant mix up his product, but that isnt because davar sheyesh lo matirin (again there is no matir for chometz shevara PEsach) ratehr becauase ein mevatlin issur lechatchila
Also the thread is not about a distributor who refused to sell, nor an assimialted Jew who sold. Rather a Tayereh Yirei Shomayim who went to the Gadol Hador and sold through him