Is there any insight as to why, apparently, a team was not dispatched to directly investigate the SOS signal? Do they problems with bogus signals, for instance?

Yes, except that they had not yet checked into a hotel in Kicking Horse. See upthread: Apparently they drove to Kicking Horse from Alberta, parked their car, went directly to the hill and bought a lift ticket, went skiing, went out of bounds, and got lost. Until the family filed a missing person report (several days later) the resort had no licence plate number to look for, and no other way of even knowing who might be missing, let alone connecting the car to the SOS.

I've not been to Kicking Horse, but if it is anything like other big ski resorts that I have been to then on a good day in February there are many thousands of people at the resort, both skiers and non skiers. There are a similar number of cars, in mulitple parking areas. Many hotels, condos, hostels, etc. Dozens of bars, on and off the slopes. People chip in and share rooms, so even the hotels and condos don't always know everyone who is staying there, but only the one who rented the room. There will even be some ski bums camping (illegally) in their cars in the parking lot. People drink too much and leave cars in the lot. Cars have dead batteries and people leave them until they can get a jump. After a big snow dump the resorts often have a tough time just plowing the lots before the next morning because of cars left parked there overnight.

Point is that there was a car in one of their parking lots that didn't belong. If it did belong then there would have been no red flag. Since they hadn't checked in, that car should not have been there.

You nailed it. To me that is the central question. Why didn't the guides who first spotted the SOS just stop to investigate?

You apparently have not spent much time at ski resorts. The resort has no direct way of knowing who or what car "belongs" there. You can drive to the resort, park your car, buy a lift ticket (cash or credit card), get on the lift and go skiing. Which is apparently what this couple did. Unless you buy as season pass, the resort has no name or other id associated with a lift ticket. Nor do they have any direct way to tell which car in the lot belongs to which skier.

Lots of people visit ski areas and don't ski at all. They drive up, park, go to the bars and resturants, and drive off when they are done eating or drinking. Again, no direct way to tell who's car "belongs".

It is also worth noting that (in the US at least) a downhill resort has no responsibility for off area search and rescue. Even if a resort has gates to let you ski off area, once you go throught the gate you are responsible for your own safety. That being said, almost all areas will try to help skiers who get into trouble off area, but they are not required to do so.

My bad, I don't do ski resorts; I don't do resorts at all.

Why did the resort personnel bother checking the parking lots at all? In the context of this "search", that seems to be a false negative. If a search means nothing, and you report the results as if they are significant and mean something, you may stop people from searching who should. In this case the "search of the resort parking lots for abandoned vehicles turned up nothing", which may have contributed to the SOS in the snow being disregarded.

That said, I agree that people in general need to take more responsibility for their own well being, staying found. But in this litigious society folks are always looking for a large group and deep pocket to blame. I don't see that ending any time soon.

Just realized that the incident at Kicking Horse Mountain Resort occurred almost 5 years ago now.

I am bowing out of any further discussion as nothing we say here will change that history and does not contribute to the current OP's post.

Unless bogus SOS signals are a significant problem, they had a glaring red flag with lights, bells, & whistles. At the very least, get a couple of ski patrol teams to check the area where the SOS was found and then send a couple of seasonal interns to check the parking lot. Being able to link a car with a missing person report only gains you more detailed information (number, name, description, etc.) If bogus signals are a problem, start with charges of reporting false information to rescue personnel if you can track down who caused it. Maybe deferred prosecution in some cases but enough to get it through that it is no joking matter (give the judge a wide latitude between min. & max).

Not sure why. If a car had obviously been left there for many days (for example buried under several snow falls) that might have aroused some suspicion. It sounds like they mostly just checked to see if any hotels had missing guests, and if so were those guests cars were left in the lot.

As hikermor said, why didn't the first people who saw the SOS just stop to check it out? Or the resort just have someone go to the location to check? That would be the obvious thing to do. To me that is the real question. I think Kicking Horse has a number of off area guiding operations (guided tours, heli skiing and snow cat skiing). Generally those outfits work closely with the resort. They might have just asked one to stop by the location where the SOS was reported.

As hikermor also said, there is plenty of blame to go around. Not the least of which goes to the couple themselves. Going out on a back country ski tour, without telling anyone where you a headed or when you expect to be back, is not smart. Doing that in an area which you are not familiar with is even less smart.