As much as the Buffalo Bills have appreciated in value, selling the 25% to finance everything seems pretty smart to me.
His net worth has been rising every year and he just sits back from now on and makes money.
As for the "investor", if it's a guy who wants to get his name in the running for a team of his/her own in the future, it makes sense.
In the meantime, he sits back and makes money for doing nothing.