1) There is something going on with this shoot that they didn’t want the usual gaggle of Lost Spoiler spies sniffing out.
2) It is rumored that the shoot required Alan Dale and he is currently doing some theater in england and this was the only way to make it work.
Beyond that, though, what are the implications for this most intriguing of Lost Spoilers? That a Ben and Widmore ‘partnership’ may possibly exist? That future Ben will be captured by Widmore? It seems that this will be revealed, perhaps, in episode 4.10.