Fixed tooltips for student views

It turns out supporting tooltips for both student & staff views would require a bit of javascript witchcraft, most likely.

Talked with Diana; it seems More Worth It (TM) to let staff view be a wee bit janky so long as students work fine.  lmk if this is not the case!

Tooltips now display the correct tooltip for students based on their test group.

Additionally, fixed the problem where verticals with multiple display_names were only displaying the first display_name.