I'd say that an anterior fusion surgery keeps hope alive that it's the scalene's vs bony encroachment. The anterior approach really does spare the structure of the neck itself when you compare it to the posterior surgeries. Either way, posture during heavy lifting, and all ADL's for that matter, is super critical. You mentioned loss of cervical extension ROM. For sure most of that is from the dbl fusion, but there's a chance that a nice 10-25% chunk of ROM is still available from a functional POV. Just have to find a qualified practitioner of worthy technique(s).
"And if a frog had wings it wouldn't bump his ass a hoppin'!"
- The wisdom of Nathan Arizona