[marcruser]

>The game says I have 3 possible words remaining, but every Wordle solver website says I only have 2

Once you finish the game, if you have any rows with 25 or fewer valid words remaining (shown to the right of the row), the word count becomes clickable. It will open a modal that will show you the valid words remaining after that stage of the game. I went ahead and entered your same sequence of words, and the the other word remaining was SOCAS. That is a valid word in the NYT official Wordle game.

>Another point of confusion is that the first row says 2318 possible words, but there only seem to be 2309 words in the dictionary in the code

There are different word dictionaries in the code.