I doubt that Fei Wong did all those. I think he expected these things to happen, and from the way I see it, all he has done is just watching the two by sending this weird waiter guy to spy on them.
Also, it seems that there is not much he can do to mess up their lives, as it would seem that Yuuko has so much more influence over that. He was quite surprised by the fact that Yuuko has the ability to twist and alter the events in time and space, so she has been "meddling" around with stuff to frustrate Fei Wong quite a bit.
Angelic- Essence's idea can be explained in this matter written below, I think...
That vault was made by an ancient group who lived well before the establishment of Clow, and Sakura just so happens to have a link to that forgotten past that is now calling out to her. Sakura's mysterious inborn powers is ancient and potentially dangerous. Maybe that's why that vault has been sealed, like a demon that has been asleep for ages, and now, seeing the light of day again, it wakes up, and then...
(GASPS)
What is that aura? It feels so familiar. So comforting. I must get more of it!!
The energy sealed in the vault and the power Sakura possesses are like magnets, and when one magnetic force is exposed to another, BAM! They stick together unless someone meddles with it and rips them apart, except that, this time, the piece "someone else" grabbed ahold of is now less than a piece.
Why is it calling her now of all the time in the world? I think that since Syaoran has been digging that place for so long, the energy from the vault itself has been released into the atmosphere, so neither is it a trap, nor is there anything anyone can do. So if anyone should blame for Sakura's fate, it would have to be Syaoran's mindless snooping and tempering with things he has no idea of.
The only fault Fei Wong is in is creating Syaoran in the first place and dump him on the street helpless and vulnerable
Again, also a speculation
