Problem with Test 14

On test 14, the test feedback says that secret_room(818) should return 4, though my (I think) proper solution returns 5. I was able to pass by intentionally misspelling eighteen as "eightteen".

I believe the door sequence should commence as follows: ["eight", "eighteen", "eight hundred", "eight hundred eight", "eight hundred eighteen", ...]

Is my logic and/or spelling faulty? Or am I correct in thinking the test is wrong? Any feedback would be greatly appreciated.