Does any1 know where captain jack was with alonso and all those past aliens?

A lot of bintang Wars references in this episode, we have the cantina scene and the spaceship battle when Wilf and that Vinvocci are on the astro lasers, it reminds me very much of the spaceship battle between the milennium elang, falcon and the tie fighters with luke and han on lasers.
I think it was probably somewhere on the outer rim, Captain Jack won't be going back to earth anytime soon I don't think, not after the events of Torchwood Children of Earth. One of my favourite scenes, with slitheeen, judoon, hath, and a little adipose, brilliant.

I'm quite sure that it was just a "Star Wars cantina" joke. and they pulled it off very well

They were in an intergalactic bar. on a planet far, far away. (someone was a bintang Wars fan)