I am a bit surprised that this application is still using flash. I thought that most Flash applications had been  transitioned to HTML 5 at this point. I wonder if you uninstall flash if the site will offer an alternative, or if possibly there is a HTML only version.

My experience has been that the only object that is interactive and accessible to a screen reader in Flash is the button. Perhaps Golden Cursor might be able to help though.

I'm working with a volunteer who is blind to access an online voicemail system through my.jive.com. The website uses flash software and we're able to access the names of the voicemails using NVDA, but we're not able to click on the links to listen to them. 

We're using a HP Pavilion Notebook PC with Windows 10 Home Version 1803. 

Does anyone have experience with my.jive.com through Jive Communications? 
Has anyone resolved issues when issue flash on a website? 

Thanks for your help!
Tim