Expandable ListView without Implementing IsVisible in the Model?

Hi,

I want to create an expandable ListView. There are many online tutorials for this, however they all involve adding a bool "IsVisible" or "IsExpanded" property to the item Model to keep track of which view cell(s) should be expanded and which shouldn't.

However, in my case, the model is a list of dynamic objects that are platform specific. Essentially, I can't/don't want to mess with the model.
How can I make an expandable listview based on an ItemTapped event (Or ItemSelected state?) without touching the model?

I've Included a link for an example of the expanded version when you CAN add to the item model: https://blogs.naxam.net/expandable-viewcell-with-datatrigger-59f5315fd90e

Thanks!