Island Tel to Peter: It's Not Our Fault!

Well, I thought things were going to work out better than this, but here’s how it went with Cindy at Island Tel.
For some reason Cindy, who seemed helpful and like she was going to work on the problem until it was solved, passed the file to Tracey. Tracey called me to find out the IP address of my desktop machine, and asked me to release the IP address so they could set up a mirror machine to see what the problem might be.
About 1/2 hour later Tracey phoned me back to announce that (a) the problem was specific to that IP address, and (b) the problem was not Island Tel’s problem, but Alter.net’s problem. She went on to suggest that Alter.net was probably blocking traffic to/from that IP address for some reason… perhaps because of “inappropriate network activity” on my part (which is absurd).
I assumed she would go on to suggest that they could just take that IP address out of commission and get me a fresh clean new one, but she didn’t and when I asked, she said they couldn’t do that because “somebody else would just end up with that IP address and end up with the same problem.”
And that was it.
If I treated my customers like this, I would be out of business. I realize that Island Tel has to make financial decisions about how much or how little they are prepared to go to support their customers. In my case, it’s not far enough. I know that if I was dealing with Kevin at ISN he would hammer away at this until I was a satisfied customer, and not because he’s a friend but because it’s the Right Thing to Do.
How can I convince Island Tel that it’s in their best interests to go just as far with just as much moxy? Or should I even bother?