Sorry, you're gonna get a lot of jokes about this.
I'll take it at face value. Could Universal buy the entire Marvel Universe? Not even remotely. Universal would have to buy Marvel from Disney and Marvel isn't for sale. I would think it's easily a 20B+ purchase if it was.
Now, could Universal buy the rights to use the Marvel Universe movies as basis for the parks? A little more realistic, but still never going to happen. Disney wants to use these characters to boost their own parks. Unless Universal's payments to Disney could be a significant driver of all parks revenue, Disney has no incentive.