What happened next? Frustrating ending
Disregarding all the religious metaphors / symbolism, and the way this film is presumably supposed to leave you wondering if "proof" of a God is possible or necessary...
What happened to the machine afterwards? Her treatment after the event was not realistic. It was disappointingly "Hollywood". Would they not have tried again with another person (or the same) to see what happened when repeating the experiment? The machine clearly was doing something unexplainable and amazing, they could see that just from watching it in action, and after spending that much money on it they surely would not have rejected & decommissioned it after just one use.
Also, the scientific community would have taken her view of events seriously, as they would have understood the plausibility of her claims, taking into account the theory of relativity and resulting differences in perception of time etc.