This is correct, Neilda. I asked, but was refused, though I gave mine.
The insurer, when I spoke to one of the claims department, said the others had "no leg to stand on."
The more I think about it, the more I think I was just a convenient excuse for one or both of the other parties. For the collision to have occurred about 10 seconds after I opened my door, then either one of the following scenarios must be true:

1) The old lady slammed on her brakes for something other than me/my door.

2) The old lady slammed on her brakes to avoid hitting my door, but 10 seconds later, the second woman hit her.

The scenario claimed by the other parties is impossible. If the old woman had slammed on to avoid the door as it opened or was open, then the shunt would have propelled her car into the door.
Scenario 2 is also unlikely, as I would have seen her approaching, and slamming on the brakes. I didn't not see any cars approaching within 25 yards, even when I was walking backwards to the back of my car. She was about 10 yards away by the time I got to the boot!