Hello Atlan
Your right, we will never be able to get close for direct evidence.
Similar with the object in a black box.
We can observe movements and processes and apply scientific know how and make decisions.
So far, we know we can see Deep Field 13.4 billion light years.
In any direction, in an area of a rice seed over 5 thousand galaxies in various stages of formation.
We are looking at billions of galaxies.
NASA tells me that all this was formed in 400 million years.
There is only one universe
Infinite in space
Infinite in matter and energy
To have a Multiverse, you need to have a TIME shift.