"Torg, did you understand?"
I got options for both bIyaj'a' and biyaj'a'. That is, the only difference was the capitalization of the I. I took a screenshot. https://www.dropbox.com/s/riivjx7pqakbo31/Screenshot_20180407-092601.jpg?dl=0
Ah yes. I've seen that sort of thing before.
The tiles are picked automatically -- we don't have control over those. The ones the system doesn't expect you to pick may have odd capitalisation, e.g. all lowercase.
I think that the system currently ignores case (unfortunately), so if you pick the biyaj'a' one, it will probably accept it as well.
Thank you for the screenshot, though! That may be helpful if I collect more of them to pass on as examples of this issue for the Klingon course.