First off, I think you really need to be a massively squeaky wheel. You bought a new stove and they gave you a damaged product. I would be on the phone every single day busting their balls until this was resolved. This is a brand new stove and you are now a month into waiting for this to be resolved.
In regards to the dolly. You can buy one for $10 at home depot. It's what I used to move the Defiant (and the Vigilant, and the Encore, and the Heritage, and the 30...).
- Take off the doors, the griddle, flue collar and anything else to lighten the load.
- Slide the dolly under the stove.
- Tilt stove to one side and have someone slide in a wood plank under stove (you can buy them at home depot cheap in their cut bin)
- Tilt stove to the other side, slid plank under stove.
- Repeat until the stove rests on the planks enough to raise the stove legs off the ground.
- The ash pan casting on the Encore, Defiant, and Heritage took the weight with no damage. I wasn't even concerned, to be honest.
- Wheel stove to vehicle.
- Load into vehicle.
I don't know how bad your back is, but, I was able to move all the stoves by myself. So, the weight is manageable.
But, I would focus on being a squeaky wheel.