I would guess that it is not the camp itself, since she's fine after an hour or so. If there is something in particular that is "off" about the drop-off procedure or the day's first activity, that could be a factor, so you could ask the camp director or assistant director to monitor her for a day or two to see what sets her off and what comforts her.
I think TF is right on the obey, though - somewhere around ages 6-9,kids figure out that they and their parents are getting older. When there's a death (could be a grandparent, could be a pet as in your case), the child's bubble bursts and they realize that no one is immortal, and bad stuff can happen when you least expect it. Some kids are comforted by religious views of death, but others just can't imagine that, say, Heaven is all that fabulous if it doesn't contains their parents and friends. They don't care if it's paradise, they don't want to go alone, and they don't want you to go there either!
I think you have to get her talking, and not just about camp and drop off and your jobs. The "How to talk so kids will listen" books have been around for a long time and they are constantly re-issued, so obviously they are popular with a lot of people. Go to the library, get a copy, and see what else is on the same shelf and covering the same topic. Don't be afraid to engage the librarian to get suggestions on what else is good for this age group - remember that you can borrow from other libraries in the same network without going to visit them, so getting good advice even in a small library opens you up to a world of choices.
For TF, watching the reality shows worked. For us, it was movies and Friday night family dinners around the table with no rushing off to do homework or watch TV or do stuff with friends. Another great vehicle (pardon the pun) is talking in the car - the kid is strapped in, she doesn't have to make eye contact on a sensitive subject, and there are no interruptions (turn off the phone). Obviously, you shouldn't do this on the way to camp, but for other trips, it's a good thing to consider.
I think it's vital not to say to kids "it's silly" or "we can't quit our jobs" (if you could, would you keep her home all day? No. So don't offer it as a possibility which makes her just hate your jobs more.). And I doubt it's about pumping up the fun of camp - that's not her problem. I do think you have to get to the root of it.
The sooner and more thoroughly you do this, the better position you will be in when she really hits puberty!