OK, close your eyes for a second.
And then open 'em, cause you can't read this with your eyes closed. :)
Now think about this: You are an alien, OK? You are one of the last of your entire species. You are desparately searching for a planet that you can live on, as you have been for centuries. The technology that keeps your species from dying out is wearing down. You have examined all of the creatures in the sector of your galaxy to see if their worlds would support you. Your last resort is a previously unknown specimen named John Crichton. You lure this Crichton into your trap, so get your "Human reaction". Unfortunately, the Human reaction you got is not positive. You realize that there is now no species you know of that can help you. You, and the rest of your species, are going to die.
Done? Now, think about *this*: The fact that your last hope--humanity or bust!--was a failure made you incredibly mad. However, you, being an advanced alien and stuff, managed to keep it under control. However, you recall a previous trap you set for a certain Sebacean/Scarran half-breed with an interest in wormholes. You realize that the perfect way to get even with this Human for killing your entire species would be to give him wormhole technology, so that he'd be toast when (not if) Scorpius got a hold of him. See, because you know that this Scorpius person has a rabid interest in wormholes, and would constantly be seeking out ways to manufacture one.
So, what am I saying? I'm saying that Jack Crichton--or his alien counterpart--got so upset at his species' death that he orchestrated John's capture by Scorpius, by giving him the wormhole technology.
Food for thought, eh?