i don't think there are any flights from wuhan to hkg on the 22nd, which is why i suggested you go to shenzhen and bus it or -alternatively- simply go to han via can. i'm not an expert on china vietnam flights, but many of my friends like it down there and have always taken cz via can so i'm pretty sure you could do the same.

if you have to go to hk, i would definitely do the szx option instead of your pek routing.

regarding hk hotels, there's no reason to stay near the airport; there are lots of decent places close to the airport express stations in kowloon and hk for around $50 per night. but, again, i suggest you do a little more research on the can option.