what UISpy or UIAVerify see are the elements which are visible for UIAutomation (and so for White).
Other Tools might show all user visible elements, (but this is not the same)
Elements which are visible for UIAutomation implement AutomationPeer.
So if UIAverify don't see these elements, UIAutomation and White don't see them.
In this case, you can try to use the new part of White
CustomCommands (i haven't tried yet)
if you have access to the developer, he might implement AutomationPeer for the element.
if you only want to click on it, you can click by position (relativ to the parent element)