Unlikely, but it could also be that they didn't torque the lug nuts properly when they replaced the wheel, and they are loose. Easy check. Just jack up the wheel where the work was done, hopefully both since you should replace both side on an axle at the same time, and see if you can shake the wheel.

There's no reason for them to even touch the front propshaft when working on the rear axle.

More than likely your front propshaft is coincidentally going out now. Even if it isn't, it will soon so you should have it rebuilt. If you have the other mechanic do it, and you need part numbers, post back, or seach for Neapco here. Parts should not be over about $70 if an indie shop rebuilds it. Probably around $120for parts if a driveline shop does it as they use list priced for the parts. Labor would be extra for both.

 

No, not unless they used the front driveshaft to jack the vehicle up. These things fail (again, ask me how I know) and cause MAJOR damage to the tune of a large hole in the casing of the transmission. That's why I sold my 2001 Disco to another land rover lover and bought a '95. I'll have to see if I can find any of the pictures.