How do I show webform component labels in a chart using Views chart format?
Module involved

About your PS:


  ... not sure which module page I should log an issue, so any pointers on how to patch the relevant project would be appreciated.


No doubt possible: Charts.

Using tooltips

It sounds to me that you should have a look at Pass library-specific options via existing #raw_options, which already provides a solution (using #raw_options) to what you're trying to get to work (ie: "tooltips"). For charting engine Highcharts it's already supported (and committed to the most recent dev version, which is the version I recommend), while for charting engine Google Charts (which you are using) you'd need to apply the RTBC-patch attached to comment nr 9. Obviously, after that patch is committed, using the #raw_options will continue to work (for either charting engine). And rest assured, this patch will (not might ...) make it.

With this #raw_options solution, Charts has a solution for using options that are specific for either of the supported charting engines (Google Charts or Highcharts). While still not deviating from a key design concept of the Charts module, which is that all supported charting options should work for either charting engines (you should be able to easily swap from one to the other charting engine, without your charts being affected).

Notes:


Apart from Webform Chart (without s), there is also Webform Charts (with s). The results you'd get are probably going to be similar, because both modules use Charts.
Drupal 7.50, which you are using, is the most recent Drupal version, but still your screenprint includes that (red) error msg with "There is a security update available for your version of Drupal"... bizarre ...


Disclosure: I'm a co-maintainer of the Charts module.