[PatrickHenry]

Could it even be possible to discover galaxies 100 billion or more light years away?

I's possible, yes. But two preconditions would have to be met: (1) such galaxies would have had to exist 100 billion years ago; because (2) the universe would have to be at least 100 billion years old, so that the light from such galaxies would have had time to get to us.

[RightWhale]

such galaxies would have had to exist 100 billion years ago

Inflation allows for recession speeds greater than lightspeed.