After the Slingbox was moved to the new location; did they adjust the network settings? Even with all of the equipment being the same, the IP Address for the router would still have changed. Depending on the Slingbox, there are a couple different ways to adjust these network settings. I'll link a few articles below for you just in case:
Slingbox 350 and before need to be fully reset:
I hope this helps!
Sling Media Technical Support