Solved

Problem with 2-tc DSQ

If your league has the tyre rule enabled, you must use two different DRY compounds in a dry race. A dry race is a race where no rain falls between lights out and the chequered flag.

You ran Inters and Mediums but Inters don't count as a dry compound.

Please see here for confirmation... NEW! League Rules Guide

Although the game doesn't see as a wet race, I was told that the dev team has changed some results, so you don't get disqualified. I asked a developer to apply this change to the race result.

At least those results getting changed I saw were results in which the tyre rule wasn't applied according to the stated rules. Also in those races the sim (correctly) didn't apply the DSQ and thus the cars could finish the race, which allowed to alter the result in the first place as only the DSQ applied by the game after the race had to be removed and thus not the result of a lap that never happened predicted.

So I'm afraid while the rules applied by iGP could be discussed this race went by those rules. It wasn't raining, not even a lot of water, if any, on the track at start, and no two dry tyre (slick) compounds were used, so the DSQ wasn't caused by a bug. Thus any altering isn't very high chance, also not fair to all those also being cought out by thinking the rules being different (wet instead of rain, two compounds instead of two dry track compounds).