I believe the Chelsea or Maresca - Jackson relationship in my opinion is already a sour one, and even If Jackson stay back, I think he'll still be surplus to requirements and might even be behind Guiu in the pecking order.
Dude was given lots of opportunities but he couldn't do anything with them. When he was the main man, what could he do with those chances that were created for him. Dude is poor in front of goal and I don't blame him for not wanting to comeback. He's not even in the two strikers at the club and will be warming the bench immediately Delap is back from injury.
He didn’t just get valued playing minutes on the pitch, he had the passes and chances created too, he just wasn’t good enough to convert, maybe for some other team but, certainly not for Chelsea and not in the EPL. It would have done him a lot of good to just leave the team but, seems the transfer deadline is reached and it’s done.
Isak joined Liverpool before the deadline struck, Liverpool might just turn out to be the most deadly team in the EPL with his signing.