If your dogs are crate trained, there should be no problem. My dog Hysson considers the tent just another crate--he curls up and goes to sleep when he gets inside (after I make it clear that my sleeping bag and air pad are NOT his bed!). I wouldn't recommend going off and leaving them in the tent, though--it might be the end of the tent!

With a tarp or a pyramid, you could tie them to something. Maybe you! Or you could take a stake (let the dogs carry it). Again, I wouldn't go off and leave them.
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May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey