After gathering a little bit of information about DNS server, here is my preliminary thought...

If you are able to have a DNS server (with static IP) that redirect the name nwcs.wapp.wii.com to one of your aibohack domain IP addresses, then I am definitely interested to test whether, by manually set-up the internet connection on our Wii (perhaps by putting your DNS server IP address as the primary DNS server in the set-up), the game could grab the DLC directly from this redirected IP address server (by allowing WiiConnect24 overnight). We could just put the guard's helmet DLC rvforestdl_us.enc file in that server, and see whether it works or not.

This will open the opportunity for distributing either custom or existing DLCs to non-wiibrew players when Nintendo stops their DLC creation/distribution. But they still need to manually change the DNS server set-up for their Wii internet connection (which
may need some holding hands to do it properly).

Thanks again for this interesting suggestion.