Wireshark would work too, you just have to look for '.m3u8' string (see img1)
and manually tweak it to get the original "master" stream . You can also install and enable a simple Firefox addon, called HttpFox, play the stream and search for '.m3u8' string...(see img2)
As for the webinars, since you don't have an example, you'll just have to try to find the correct string on the fly. I'm sure wireshark and HttpFox, will have it.. Cheers!
img1
img2
