Hi @Joseph Chapman,
Thanks for your patience so far!
Actually DevNet documentation you're checking here is pretty old, though I'd say there is pre-built JIRA App for Customers to use directly.
You should check the details actually from Webex AppHub portal here - https://apphub.webex.com/applications/jira-cloud-34441-68681 which should give you a clear idea how this App or, precisely this Bot works.
This indeed help to create or, update a JIRA issue and also fetch specific JIRA details of your Org's defined projects.
However, please make a note - to be able to use this JIRA Cloud Bot with your Webex account, you need to setup this Bot on the Webex space (1-1 space or, Group space) and during the setup process, you have to authorize through your JIRA Server Account.
Also, make a note - this JIRA Server account which you'd be using for setting up the JIRA bot, should have administrator access on JIRA.
Please feel free to reach out to us know for any further assistance.
Regards!
Sandip