ok, my
experience with slimy is more from making kimchi- i was taught not to put too much ginger or it would be slimy (too much garlic: bitter). But I see from reading
online that it seems every kimchi maker has their own explanation for the slime, so i'm not sure!!!
what does seem to be universal is that more salt and a longer salting period usually helps. i'm not sure how much this applies to ferments other than kimchi. the garlic, personally, i'd rinse and make a new stronger brine to cover and see what happens (my garlic pickles come out crunchy, but I usually pickle it in soy sauce).
As for the cabbage, i'm not sure. Sometimes the top just looks really nasty, but the cabbage underneath is fine. It's only been two days, so it's still early to tell how it's coming. How do you have the sauerkraut covered? You have something pushing it under the brine (could be a cabbage leaf)?
Two days is pretty early to make any decisions about a ferment (unless it smells like rot), so don't lose hope yet!