I’m not an expert on audio, nor am I a guru.
H.264 is a video encoding specification, not a container. Your container can still carry audio in as many channels as your software allows. It can be LPCM, Dolby, whatever – different encoding. E.g. MOV container, H.264 video, LPCM audio.
To match Prores 422 you will need at least 50 Mbps or more. You might want to factor in additional upload and download times based on the Internet speeds at each location. Four hours at 50 Mbps is about 50 to 100 GB. The total bandwidth is equal to your upload plus each download. A CDN will let you manage this easily, but it might cost about $1 per GB of bandwidth, with storage extra. Try speaking to Akamai. A yearly plan might give you a better deal.
FedEx also has a business account deal with huge discounts, try that as well.
Hope this helps.
https://www.wolfcrow.com – Workflow information and support for filmmakers, photographers, audiographers and videographers.