You have a better chance of the lottery than "reasonable" with the first 3.
Not sure why you're lumping Holliday, Henderson and GRod with the Rutschman. I think you can extend Adley. I've suggested a contract and if they offered to him, I'd surmise he'd sign it.
You want contracts for the other 3?
GRod 12/330M
Gunnar 15/500M
Holliday 20/705M (and you get to defer 300M)
Bottom line is use them while they're here. Build the next layers. Have a plan. Success isn't tied to any of them. If they're part of it, great. If they want to be part of it longer term (beyond club control), great. If they want to pursue other goals, whatever, win without them.
I'd sign G-Rod to that deal.
I wouldn't sign Gunnar to that many years, but I'd give him that AAV over 10.
I have no idea why you think they'd have to give Holliday 20 years to stay here, but whatever. If his goal is to maximize his career earnings, he's much better off taking 350 million or so over the first 10 years of his career, and going for another 300 or so in the back half.
Regardless though, I feel like talking about contracts with you is an exercise in futility, because you're convinced that you know more than anyone else what it might take. I don't mean this disrespectfully, but I don't think you're any more accurate in predicting what it takes to acquire players, or what it takes to sign them, than anyone else who spitballs those numbers around here. I don't believe the Orioles would have to offer something that insane to get an extension out of any of those players, but it's not my job to know.
Bobby Witt Jr set the market for what it takes to extend a young star infielder. What he got isn't even in the realm of what you're suggesting for either Henderson or Holliday, and he has as good or better a resume as either of them.