2019 .PST to 2024 .PST.... boom Corrupted!!

hi Eric, I'll try to help. If your original PST is very old it might not transfer well. I have had to make a new PST to get it to convert. I don't help clients with the reg edit to max past 50 gigs, I try to help them balance with many PST's versus one that size. The size might be the issue as well. What I would do is create a new PST, then move some of the larger folders to the new PST. I always make a backup before moving any folders or emails from a PST to have a safer move. As you have a custom PST, it could have issues with moving to a new one. Just a pro tip here. 

I don't think ScanPST would repair this, I would export the entire thing to a new one but as you have it at 70 gigs, it probably won't export well. 

My opinion is to make a new PST and move folders to balance the load.