This is what happens in books like this, the authors like to fiddle with the recipes giving them their personal touch ruining the authenticity. This is a rather well known recipe to Norwegians. The sauce here, which in Norway isn’t even called a sauce, but “Eggesmør” (egg butter) is wrong. I’ve just been checking through several dozens of recipes. Some use just eggs and butter, some cream, eggs and butter. Some chop the eggs finely, some roughly. Some add chives, some parsley or dill. But no one but no one uses broth or tomatoes.
I’m sure people from other countries have found their local recipes have been fiddled with too. But having said as much, you really should try this recipe, it is simply delicious. Just leave out the broth and tomatoes in the sauce/egg butter.