Lets hope that they are sleeping over an extra day without any cell coverage!!
Anycase, strongs and keep us updated. I think his wife must be going crazy by now.
Ain't there anyone in the Cape Town area that can jump on a bike and start searching for them?
Not a very good idea before you know very well where they went missing (which road, which section).
I had customers gone missing in the Cederberg before and have some experience about how to organise a search.
For now / first:
Find out where last seen and heading which way.
Check with farms / settlements en route after the last seen position. (In my case a child in Wupperthal could ID the bike confirming than they had past W. and were somewhere between W. and Calvinia).
If they are likely to be missing in the Cederberg proper contact the accommmodation places like Cederberg Oasis, Mount Ceder, Kromrivier, Driehook etc. Explain the situation and ask if they can inform all guests which go out today (plenty 4x4 this time of the year) to look out.
I sincerely hope rider and pillion are in one piece and only stranded without fuel or broken down (it's a KLR

)
Unfortunately my experience with SAPS Clanwilliam was some sort of a "could not care less" attitude but things have hopefully changed since then.
BTW: My people forgot to fill up, ran out of fuel and had to seek shelter from exposure due to a frikken snowstorm coming down. They were found 10PM with the bike on the side of the road and them having broken into a farmhouse.