This is not possible with IsInPageList as is. Here are a few suggestions
You could create your own Rule-Utility-Function that adds an additional while statement if you will always be evalutating just two levels.
If you want to recurse and find that value anywhere in a whole heirarchy, you could have the RUF call itself.
You could try using pxRuleSearchClipboard and see if that works for you, but it will return JSON of the list of all the results where that string is contained in any property (not equals in a specific one). This is probably not want you want, but it's worth mentioning.