Why do you want to lose the item with your higher bid if it's not accessible on eBay US, but accessible everywhere else? This seems like a very specific to your own use case only.

If you could bid on eBay.com, you are usually fine unless seller makes some change or eBay moves it (which is rare).

I don't know about Android app, eBay may handle it differently since they use eBay API for that, not direct communication with their website.