Am I a ninja?

This is on the Lordaeron realm and occurred 5/27/2020.

I created a 10 man raid group for Ulduar specifically so that the raid group could complete the {Flame Leviathan Must Die!] quest. After successfully killing Flame Leviathan, the items [Lifespark Visage} (cloth caster helm) and {Pyrite Infuser] (mdps trinket) dropped. I told the raid group that I would consider main spec before off spec for rolls because I believe that to be fair.

No one rolled on the [Lifespark Visage} so we disenchanted it and rolled for the abyss crystal which I fairly won and kept. After, three people rolled on the {Pyrite Infuser] and before I gave it to the highest roller, I examined his gear to ensure that he was main spec mdps. The winner was a death knight whose gear was a mixture of about 4/16 pvp pieces, 11/16 pve dps pieces, and 1/16 tanking trinket. In addition, his spec was unholy which I consider as a dps and not tanking talent tree. In that moment I assumed he was in fact main spec mdps as some pvp pieces can be used for pve content and therefore I gave him the trinket.

After I did this, I was immediately called out by some of the raid group and someone even called me a ninja for giving him the trinket and threatening to report me, claiming that he was main spec tank and that I should have known.

In my defense, Flame Leviathan does not require any gear and can be done with any composition of specs as the entirety of the fight is within vehicles with a fixed amount of damage and health. So therefore I think that I wasn't a ninja in that I couldn't have known that the dk was a main spec tank, and the gear that he did have on convinced me that he was a main spec dps instead.

My question is, would I be considered a ninja in that situation?

In future Flame Leviathan raids I will ask people their MS to try and avoid this situation in the future, but I didn't think it was necessary at the time. Usually I only have to ask people if they're rolling for a spec that they're currently not performing as in the raid. An example would be a tank that going to be tanking the boss telling me beforehand that they are rolling on dps items instead, which I would accept.

Thank you for considering my issue and I hope to hear an answer soon.

You'll be fine. FL is a vehicle only boss and if the dude did indeed have only 1 tank trinket and the rest of the gear dps he was dps indeed, probably took the tank trinket for the gs (assuming it was some icc dungeon trinket).

@Thorbjorn Thanks for the insight man. In retrospect I think that the people accusing me of being a ninja were just mad that they didn't win the roll and wanted to find any excuse in order to get another chance at it.

In the future dont even bother to put master loot for weekly quests in ulduar, nax etc...