Tooltips with string data fail on GridMatrix

Hi! This is my first day using HoloViz, so I’m sorry if this is an easy answer.

I’m trying to make a GridMatrix of scatter plots to explore multivariate data.

I’d like to be able to find some string name or ID associated with certain points if I hover over them.

I’m successfully using the Bokeh HoverTool to display the numerical data from the vdim categories in the GridMatrix.

However, I haven’t been able to display the solvent name. I’ve tried storing this as both Pandas object dtype and the StringDtype with no luck.

I’m worried that this behavior is a side effect of the GridMatrix not supporting categorical datatypes as mentioned here: https://gitter.im/pyviz/pyviz?at=5d236d460b07314d50261f3e

Here is a screenshot of the plot and the relevant code:

Thanks for your help!