I wonder if we can use the Premier League as a rough comparison of how it could look in the NHL. I haven't read too deeply into how the Premier league managed the players during the time gap, but they were testing before they started play again on Jun 9th. results are here:
https://www.premierleague.com/news/1670563
Since the start of play, they managed to keep the weekly results from 0 to 2 positive results.