Personally I'm beginning to have doubts about a 2019 opening, and that was before the hotel announcement.
You just look at the site, and therest still so much to do. The coaster isn't finished yet. There's not even a glimpse of any theming aside from the wall. Compared to Klugheim, which at this stage had Taron track complete, Raik track almost done, and a lot of theming, it seems like an awful big job to get it done for, say, summer 2019. Especially if we're getting the high level of theming that we expect from Phantasialand.
I'm not ruling it out (remembering how Black Mamba looked less than 2 months before opening always fills me with hope), but I'm feeling less confident than I did a couple of months back to be honest.