Can I boil bratwurst in beer to cook them?
Assuming that they are uncooked, you can certainly simmer your brats in beer (don't let them boil, that will burst them). I'd try to get a hold of some Red Hook and use that. Simmer them gently until they are almost done, about 15 minutes. Simmering in beer will only intensify the beeriness of the brat. If you like beer, go for it. If you've got time, do one in advance and see how you like it. You can dilute the beer with water or broth if you find the test brat too strong.

Consider adding some whole spices, garlic and onion to the beer and simmering them for 10 minutes before adding the bratwurst. Here's a recipe for exactly that. (That recipe looks outstanding, BTW)

Cover the pan and let the almost cooked bratwurst cool in the beer (seasoned or not). The recipe I linked to says to cool completely, but just 20 minutes or so is plenty. By then any carry-over cooking is done, but the brats would still be warm.  Then just grill or brown on the stove just for browning, they will already be cooked through, so it's just the browning that you're looking for. Just let your eyes be your guide and don't go past medium heat (again, they will burst if your heat is too high).