I would think an exported results in json format should be able to dropped back in to postman to be opened. This might not answer the question. However, I found out that you could go back to your collections runs to see the history and it kept the results there.
Go to left nav click Collections >> Click collection top folder
On the main display pane which shows the "Overview", click the "Runs" tab.
This now will show your previously run collections results again.
Now click under "All tests", it will list all test and the results.