We’re talking about a multi-purpose microwave (all kinds of food are heated in it).
There was a bowl of soup with meat in it, with a plastic cover “protecting” it—a cover that we use for dairy foods heated in the microwave.
The question is about the cover,
and really also about the bowl (which I currently can’t identify, because it got mixed in with other bowls).
Thank you very much.

It seems to me that if it reached a boil, the bowl and the cover are forbidden. I’m not addressing the question of absorption by plastic (in light of Pixler’s research findings). I don’t know what they concluded regarding plastic.

With your permission:
A. I don’t know whether heating for 2 minutes in a microwave is considered boiling.
B. The bowl in which the food was cooked got mixed in with the other bowls, and I don’t know which one it is. What is the status of the bowls?
C. Does it matter that the plastic was not used within the last 24 hours? Can the utensils be fixed by purging in boiling water, or is purging ineffective for plastic?

A. It seems to me that yes. It reaches the temperature at which the hand recoils.
C. If it had not been used within the last 24 hours, there are opinions that the utensil is permitted. Especially if it was poultry and not meat, it is more lenient. Plastic cannot be purged in boiling water.
B. If there is substantial financial loss in having to throw out all the bowls because of the doubt, one can combine the fact that the utensil had not been used within the last 24 hours and permit it based on nullification by majority (even though this is an identifiable utensil, which on the rabbinic level is not nullified by majority).
That is my humble opinion.

Thank you.
Regarding section B, “if it had not been used within the last 24 hours, there are opinions that the utensil is permitted”: do you also mean the plastic cover, under which no dairy item had been heated for 24 hours, or do you mean only the bowl that contained the meat (not poultry)?

What difference is there? The cover is more lenient than the utensil itself, since it doesn’t touch the meat.