Hello, my name is***** and I have over 20 years of experience as a veterinarian. I am sorry to hear that your pups got themselves in to trouble.
The butterscotch chips are high in fat and sugar, so they will lead to an upset stomach, vomiting and diarrhea in many dogs, they aren't technically toxic.
Semisweet chocolate can be a problem however depending upon how big the bag was, how much your pups weigh and how much each dog ingested. Semisweet has more of the toxins we worry about in chocolate compared to milk or even dark chocolate.
Signs of chocolate toxicity include drooling, nausea, vomiting and diarrhea, then hyper-excitability and an elevated heart rate.
At higher amounts we can see muscle tremors and possible seizures. A 50 pound dog would only need to eat 3 ounces of semi-sweet chocolate to see signs of nausea, vomiting and diarrhea, and 6 ounces to see an elevated and irregular heart rate, and 9 ounces could cause seizures.
If this occurred within the past couple of hours it is well worth inducing vomiting.
You can give each dog 1 tablespoon of 3% hydrogen peroxide per 10 pounds of body weight soaked up with bread or a small amount of food. No more than 3 tablespoons even if they weigh more than 35 pounds.
Then take them outside and run them around to get the peroxide bubbling so they vomit.
If no vomiting in 10 minutes repeat the peroxide dose once.
If they vomit and seems to clear their stomachs I would check to see if most or all of the chocolate is present.
DO NOT let them eat their vomit.
If it has already been 2 hours it is likely the chocolate is out of their stomachs and it is probably too late to induce vomiting. At that point you cannot change things much at home, all you can do is watch for further symptoms now.