This stadium has a movable roof. That might help.
The problem I see....you open up the stadium and maybe no fans in the stands would show up for 3 games over eight hours. There’s zero profit for the teams under these circumstances.
To make this work, you’d have to have four (maybe five) stadiums being used like this (maybe in San Diego, Tampa, and Atlanta as well)...with teams only playing ‘grouped’ teams...meaning no travel. Less risk of transmission.
Losing interest around the rest of the US? I think 70-percent of us would shake our heads.
The Phoenix area has 10 spring training stadiums, plus Chase field for 11 fields. They only play 15 games a day at most, so 3 parks would need to play 2 games per day to make it work.
The money will come from MLB’s current TV contracts. It is a considerable sum.