Doug Burgum brings money to the table. Trump's fortune is under assault due to the unrelenting lawfare against him. The Republicans need lots of money to run a successful campaign. Corporate America has largely switched to the Democrats with the exception of the oil and gas business. Burgum can help finance this campaign and if Trump wins he has the best shot for the 2028 GOP nomination.
There are loads of other ways to get money to Trump’s campaign via various PACs.
If we’re to the point of selling the veep role to the highest bidder, that’s a sad situation indeed.