My ex bought a car under my name with Honda Finance and never made payments. I sent about 5 GW letters and kept disputing with the CRA's as incorrect info (they had it as a repo but I voluntarily surrendered the car which should be a different classification according to EQ). After about 4 months of doing that, they magically deleted it from all 3 CRAs! Then a few weeks later EQ out it back on, but showing no late payments, current and paid and satisfied!!!! Figure the logic in that one.. Anyway keep trying by sending GW letters out every so often, use as many different addresses as you can find, and hopefully you find someone on a good day 
I used the GW letter here on the forums and revised it to include my sad divorce story and I guess it worked.
I used the GW letter here on the forums and revised it to include my sad divorce story and I guess it worked. Good luck!