tertiary dropdown menu not working

I’ve got a three tiered vertical navigation menu that doesn’t seem to be displaying the last tier of the menu. I’m using bootstrap in the underlying architecture and have only one three-leveled dropdown menu. I just can’t see that last level or tier. Here is a link: http://staging1.thestudio-patrick.com/wordpress/. If you click on Investor Relations, the dropdown opens fine. But “Company Info” and “Stock Information” are (or should) also be dropdown menus. You can see it if you view the source code or inspect it. I’ve exhausted all resources I know to figure this out. Hoping you can help!