Alternator/generator/regulator problems of the 2010 Jeep Commander

The battery light came on about 5 minutes after I started driving through residential streets and onto a freeway. I exited the freeway and went to the auto store where I had originally purchased the battery from, about a year ago, which is less than 5 miles from my house. They tested my battery and said the battery was good but my alternator was bad. I drove my Jeep Commander home and parked it in the garage, per usual. When I exited my Jeep there was no odor, no smoke, no sound of any sorts coming from under the hood. Less than 20 minutes of parking my Jeep, my Jeep was on fire and caught my house on fire. No warning nothing! my Jeep was 10 years old and just turned 103,000 miles. I faithfully serviced my Jeep at the local Jeep dealership or midas. My Jeep had no previous issues of any sort (no loss of power, no leaks, wasn't running hot, etc. ).