Regarding the story of Yekezkel, that he was Machmir on himself on the meat that he would eat. The Gemaruh asks why wasn't Rabbah also Machmir on the meat that was " She'horah Bah Chacham "- to be strict not to eat meat brought for a decision before a Chacham. The Gemaruh ans. the question there. In fact the Remah paskins this way Y.D. 116:7 - an animal allowed by a Chacham through reasoning, where there is no explicit Halacha, a Baal Nefesh should refrain. As far as I know, this is the only Chumra of Yekezkel that is mentioned LeHalacha, for a Baal Nefesh. The other Chumrahs that are mentioned not to eat a Mesucenet or to give Matnas Cehuna from an animal, EVEN if the owner is a Cohen, are not mentioned. Why not ? If a Baal Nefesh is to be Macmir, shouln't he be Macmir on all the items ?
As a matter of fact, the Chumra of Mesukenes is mentioned in the very same paragraph of Yoreh Deah which mentions the animal allowed through reasoning. The Chumra of Matnos Kehunah is also brought in Shulchan Aruch (Y.D. 61:5, see Biur Hagra who says clearly that the source is our Gemara).
All the best,