Do you know anything about your transport once you're in Hofuf?
As your transport and accommodation seem secure, I don't think that you should worry about terrorism. The road between Hofuf and Dammam is also considered safe.
In terms of terrorist threats, as with all things, rare edge cases do exist. It might be best to restrict your movements more for the sake of ease of mind.
For more context, you might find this Expat Arrivals page on safety in Saudia Arabia useful.
This Expat Arrivals page on the eastern province of Saudia Arabia might also be informative. Apparently the dates in Hofuf are exceptional.
I hope this helps.