Need to stop timeline when Engage Interaction is launched from Top bar of player

This is all using Storyline and Engage 360. The course will be published for LMS.

Here's what I need:

• A glossary that includes formulas in the definitions
• Access to the glossary on-demand

Here's what I did:

• Created the glossary as an Engage Interaction
• Imported as a new slide in a new scene at the end of my Storyline 360 project
• Did not link the scene to others
• Added the glossary to the Player top bar and set to open as lightbox

The problem:

The slides of the Storyline project all have audio narration and a timeline full of objects synched to the narration. So, I need the timeline to pause when the glossary is opened. Right now it keeps playing behind the lightbox so the user is missing out on the content.

Any ideas on how to make the timeline pause?

If not, other ideas on how to solve my initial need would also be appreciated. I do use a table of contents / menu in the player, so another option is to just access the Glossary Interaction slide from the menu, but I'd prefer not to go that route as it is less user-friendly. I cannot store the glossary as a web object outside of the LMS because of our business model. I also cannot post the project here, but could mock-up a similar idea if people cannot recreate my issue.

Thank you!

PS The plan is to add a second Engage interaction using the same method, so I'm really hoping I can make this work.