I don't doubt. I'll take your word for it.
And to be honest I didn't even check the stats nor I attempted personally to fight/kill it, because that's not really the point.
The issue is precisely to have everything "leveled" to your range (leaving aside if the number is sincere or misleading as in this case) and, as I said, I find questionable the very fact that a level number is showed explicitly to begin with.
Also, I'm admittedly being introduced to 5th edition just recently, but as far as I know in past editions monsters in D&D weren't supposed to have "levels" at all, just a vague difficulty rate.