A yeshivishe fellow with a hat and a beard was standing first in line at the fresh frying egg station during chol hamoed in a hotel when the gas of the canister of the portable stove ended. Following the established instructions for kashrus the cook summoned the mashgiach to turn on the new canister to avoid bishul akum. The mashgiach was busy and the fellow who had already waited a long time offered the cook that he could turn on the fire. He did so, and then the mashgiach came and was very upset that protocol was not followed. He went to the fellow who lit the stove and after he had already eaten half his egg, he told him that the remainder is ossur since he depends on his kashrus. The fellow went on and finished his egg and the mashgiach publicly, to stress his point, took the plate and angrily placed it in the garbage can. Who was right?

Shulchan Aruch (Y.D. 127: 1) rules that a single witness is normally not believed in regards to the state of kashrus of food if the owner contradicts him and says he knows the food is permitted. Particularly in this case since the mashgiach presumably did not even prohibit the eggs as Bishul Akum, rather his intention was to maintain and enforce the kashrus protocol in the eyes of the personnel.
Horav Shlomo Miller’s Shlit’a opinion is that the Rav Hamachshir in charge of the Kashrus operation, should be the one to render the decision since other issues may also be involved

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a