It says that they are Not the primary insurer and that you should file any and all claims to your primary insurance first. .
I think that you will find that almost all insurance policies say something similar. I'm in Canada. Here, our Provincial Health Care Plan would be considered the primary insurer. Any supplemental insurance, whether it be insurance through your employer or insurance you purchase separately, will all likely only cover the costs not covered by the others. Even insurance provided by long established companies like Blue Cross will do this.
Another common condition is that most of these insurers will insist that you call them first in the event of an accident. This isn't because they're your best friend. This is because they want to control your treatment... i.e. they want to control how much that treatment cost. Since we started this off talking about skiing, if you happen to bust your leg skiing and head off to the local fracture clinic, but didn't bother to call the insurer, you might find yourself out in the cold... Even if that fracture clinic was one of their "approved" facilities. I have always assumed that this was because they have negotiated treatment discounts from these places.
I think it's a little less complicated her in Canada because the government health plans publish their charges for all to see. A supplemental insurer would know what they're on the hook for if you are for example, an American skiing in Canada. Mrs. Stoo has busted both of her legs while we were out of province. Twelve years ago, while skiing at Lake Louise in Alberta. (We're from Ontario). Upon discharge, she got a bill for crutches and an extra set of x-ray films to take home. This summer, she broke her other leg on a dive boat while we were in Quebec. Again, she got a bill for crutches and an ambulance ride.
Getting back DAN... We contacted DAN as soon as we arrived at the hospital. Mrs Stoo was experiencing numbness in her extremities. I didn't think it likely it was DCS given our profiles, but I wanted a second opinion. Towards the end of that conversation, the person I was speaking with at DAN asked if we were going to need assistance getting home. That wasn't something I had even thought about at that point!
Anyway, to make a long story short, a week later, after she had recovered from surgery to have a rod inserted into her tibia, DAN flew a nurse to us (from Toronto to Gaspé), set her up in a hotel, and then paid for four seats to fly them both home. (Three for my wife, so she could keep her leg elevated.) They emailed every couple of hours through the week to see how we were making out, and to ask if we needed anything else. Their service was nothing less than perfect. My guestimate of the evacuation cost... flights, hotel, nurse and even a limo home... was likely in the $12,000 range. No muss, no fuss.
Driving my wife home (20 hours without breaks) would have been painful and dangerous for her. I honestly can't say enough positive things about our experience with DAN.