Sounds like they didn't acid etch enough, or at all. You only get bubbling on it from minimal prep work. I hope you didn't pay them much. I'd say see if they will come back and fix it. But seeing as they screwed the initial job, I wouldn't exactly feel good letting them screw it up twice.
Also, some epoxy sets like that will bubble over time from warm tires (if you park in the garage). Griot's Garage is the only one that consistently gets high marks. The Rust-O-Leum one's are garbage, even if you acid etch the concrete, over time hot tires will cause imperfections.
