First, run your game again, select Kelsey and press K. See if this fixes your problem.
If not, try to do this:
Uninstall Kelsey fully. Delete all Kelsey-related files from your BG2 directory, but _before that_ make sure there's no mention of Kelsey in your Weidu.log except for "recently uninstalled". Download both mods again, make sure Kelsey and Kelsey-Tob downloaded successfully and fully. Then close the game and all game-related utilities, and run Kelsey-SoA(just Kelsey-SoA for the moment) again, do everything the install requires of you. Make sure Kelsey-SoA is now in your Weidu.log. Make sure lots of files named like *klsy*.wav are in your override folder now(if not, reinstall the mod). Then run the game from the point before you enter the Government District for the first time. Enter the Government District and meet Kelsey. Should work. If it does, you can exit the game install Kelsey-ToB in the same manner.