Words with Friends has added words
In the past, JA was not a word in Words with Friends, but now it is.
I also have WAH played in a game by another player and the words with Friends word Radar shows that three letters can be added before WAH to create a word ending in wah. My letters are LASHSNM. Annagrammer's Words with Friends cheat shows no words ending in WAH. I have discovered MWAH works, but haven't figured out which three letters of my seven can be used to make a 6 letter word ending in n wah.
I found both of these in one game, so I can only assume they have added words that aren't part of your database.
Thanks for the help.