I've just been on the UK site and you can only see any reference to these sets if you're logged in and search for them by part number. Was this the case before?
It seems so now, but that wasn't the case before the odd shutdown of Halloween I posted about.
I originally found these just by looking at the DS stuff, though the pics didn't come up unless you clicked on the item to expand it.
Yesterday I was putting together a DS order, and couldn't find them anywhere on the site - but as you say, with the set number as given above, you can (supposedly) fast order them anway. I added some to my order to test, and they came up with the correct descriptions and prices, but I didn't actually order any this time round, so I don't know if they're really available or not.
My guess is they were put up briefly, but when the links didn't work properly they took them down again for maintainance, and they'll appear again soon. Meantime they can still be DS ordered using the set numbers.
I wish the Playmobil site had a "show me everything" choice. Searching by themes means you can easily miss something. From the farm theme I ordered a dovecote for my castle, and some sheep for my shepherd (he's only got a herd of one at the moment, poor chap).