It looks like the cap from the racking cane is stuck inside the siphon, is that correct? Mine comes apart rather easily (my racking cane) but my siphon/thief does not. With my limited experience with these items it is difficult for me to diagnose the issue with the limited view of the pic, maybe if we could see the whole tubes or the other ends as well we may be able to diagnose more effectively. But from looking at mine, if you are able to get the safety cap closer to the end of the thief (again looking at mine) you should be able to pull it out with some needle nose pliers or something like that. Good luck, hope you dont have to destroy anything