In exactly the same way that Gary Ablett had a contract with Geelong in 2010 but had signed a contract with Gold Coast for 2011-2015 at the end of 2009.
It has nothing to do with the uncontracted player clause.
1) There was an "agreement" that Tippett could "go home" at the end of 2012 for reasonable compensation (i.e. similar to what we would have received if Kurt agreed to go to the Gold Coast as an uncontracted player at the end of 2010).
2) Gold Coast decided at the end of last year that they would bring Kurt home at the end of this year and a contract was signed using the "loophole".
Did you hear Phil Harper on 5aa when asked about the "alleged agreement'. The AFC has been very careful in how they have worded their answers on this matter. Why wouldn't they simply say it is crap. Well when this all comes out at the end of the season the answer to that will be obvious.
There is a part of me that suspects you are just trolling Rucci, seeing if he runs a completely fictitious story. But assuming what you say is true, there are still a couple of bits that don't quite add up.
Mainly, the Ablett situation in 2009 was very different to the Tippett situation in 2011, and it has everything to do with the uncontracted player clause.
In 2009, Ablett was contracted to Geelong for 2010. However, the position was that if Gold Coast and Ablett came to an agreement for 2011, it did not require any agreement on Geelong's part, as the Gold Coast were entitled to take him as an uncontracted player without having to trade with Geelong. For Gold Coast's purposes, as at 2009, Ablett was effectively a Free Agent in 2011. They signed him in 2009 (not sure if that's actually what happened, but say it was), and it was done. Nothing Geelong can do about it.
Contrast that to Tippett's situation in 2011. He, like Ablett, was contracted to his current club for 2012. The difference lies in the fact that Gold Coast have no right to just sign him up for 2013, like they did with Ablett 2 years earlier. The only way they can do it is by trading with Adelaide or by Tippett walking to the draft. Tippett is not a Free Agent.
So point 1, any agreement couldn't have been made "in exactly the same way that Gary Ablett... had signed a contract with Gold Coast for 2011-2015 at the end of 2009."
Now, as for the agreements you set out in your numbered points 1) and 2), on my understanding of the AFL rules, neither would actually be enforceable. That's not to say the agreements don't exist, but my understanding is that all AFL contracts have to be ratified by the AFL and that any side agreement can't be enforced - putting paid to agreement 1). As for agreement 2), GC and Tippett might have come to terms, but any such contract would be based on a condition precedent that either Adelaide trades Tippett to GC or Tippett allows his contract to lapse and is drafted by GC. Either way, teh contract could only possibly come into force once Tippett is actually a GC player, which is not something that is actually within Tippett or GC's control.
So what I'm trying to say is this: these agreements you speak of may or may not exist, but if they do and the Crows don't like them, they can pretty much just ignore them. And if they do that, any "deal" Tippett may have done with Gold Coast is not worth the paper it's written on until they actually come to an arrangement with the Crows or take their chances in the draft.