Viking is like the sister company of Continential right? So the quality should be almost the same.

That is also because the rubber compound is not having good wet traction. It's a hard compound made for longer lasting but no good for anything else!
To the contrary, as per my comments above, the CC series actually is a very durable tire that will last very long coz it's using harder compound BUT the grip either dry or wet is very poor! Good performance tires always use relatively softer compounds (tread wear rating 320 or below), that's why the rubber can grip the road surface much better, but they would not last as long. Harder rubber on the other hand would not grip as good, as evident also when tires are getting older and the rubber gets even hardened, the grip level keeps deteriorating. Dunlop like any other tire brands also makes all ranges of tires, from shit level ones similar to the Continental CC series to the high performance ones (Dunlop Sportmaxx series), so you cannot just generalize that Dunlop is better. You need see what product range and compare apple-to-apple.