I don't have back issues, but my back would burn out at first on this exercise.
You just have to try it with the lightest band.
If you can't, the other option I can think of is installing rings on a beam in your garage and somehow attaching a band around you and something on the ground.
Rings can be adjusted to hang low to the ground so you can do rows at an angle facing up.
Attaching the band to yourself and an anchor on the floor is the tricky part. I don't really know what to tell you about that. Perhaps you could ask someone to step on the band as you do that one set for the exercise?