Using Accessibility ID on a "Popover" window

I have been having a torid time accessing elements with Accessibility Identifiers in a “Popover” window (on iOS. XCUIElementTypePopover)

I can access the elements using -ios class chain.

Should I expect to be able to use Accessibility Identifiers on these windows? I would have expected so, but it has happened twice now that I cannot use Accessibility Identifiers on them.