To access the needed item from the RibbonBarDropDown you can find it by its index. For example the following code returns the text of the first RibbonBarListItem:
//here I find the ribbonbar first
ribbon = $find(
//here I get the first tab, the first group and then the third element in the group which is the RibbonBarDropDown
//then I get the text of its first item
To adjust it to your particular scenario you might need to change the indexes of the tabs, the groups and the items.
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