Jaylen will be offered an extension, but it certainly won't be for the max. My guess is somewhere around 4yrs/$90M and Jaylen will probably just wait.
It would probably be smart for the Cs to just match whatever contract another team offers for both players (unless Tatum just blows up this year - Jaylen's extension negotiations will take place this off-season). At the very least, if things aren't working out, they are only on the hook for 4 yrs and 5% raises rather than 5 yrs and 8% raises.
That could be penny wise, pound foolish, as the saying goes. (One of Danny’s flaws, I think). If those two are getting the max by another team, they’re not getting offered a straight 4-year deal with raises. They’re getting offered a 3+1 deal with raises and a 15% trade kicker, so that if you match, and they become the player you want, their contract expires a year early, with them remembering how wouldn’t pony up the first time and probably leaving as UFAs.
If you think they’re going to get the max in free agency, you pretty much give them the max now, as a designated rookie with the 5-year deal, or you trade them to a team that’s willing to max them. Long run it’s probably cheaper to get them on a 5-year deal on the 25% level than a 3-year deal at the 25% before jumping to 30%. If you’re not sure that they’re worth the max, and that’s causing you to hedge, again, trade them, because there are teams who are willing to go there.