Yep, the above comments are correct. I doubt you have much recourse with the shop though, especially if they provided you with a work order that has a note to come back in 50 (or 100, etc.) miles to have the lugnuts re-torqued. Unless you can demonstrate that you did not have that amount of miles on the truck since they installed the wheels.
Additionally, since you noticed something unusual but continued to drive the truck without inspecting for the issue, you likely allowed more damage to occur than if you had inspected for the issue immediately. This would be a good rule of thumb going forward.
I'm glad no one was hurt as a result of this issue.
-Rod