Are they bare root or potted? Have they broken dormancy?
Whether they are bare root or potted, them drying out is a big risk but bare root are obviously more at risk. You want the roots to stay damp but not so wet they rot. If you can't get them in the ground immediately, which sounds like you can't, pot them up.
Freezing is not a problem as long as they have not broken dormancy but if they have broken dormancy they need to grow and store energy before they go dormant again. When you say they have wilted that makes me think they have broken dormancy. The best thing I can think of is to pot them up and try to keep them alive until you can move them outside.
If they have not broken dormancy protect the roots from drying out and store them someplace pretty cool.
Can you online track them? That may give you a clue as to what happened. In the absence of any evidence I'll postulate a theory and let you blow holes in it. They were mis-delivered to a neighbor who dropped them off at your place without notifying you. Hence the mysterious Monday morning delivery. A responsible nursery should have shipped them early enough so they arrived before the weekend to keep them from drying out.
I recently got some fig trees from Stark Bros. They arrived fine and all that. They said they would send me an e-mail when the trees were shipped. That e-mail was sent just a couple of hours before the plants were delivered. If I were not retired and happened to be home to receive them I could have been a bit upset, especially if my dog had gotten into the packages. I have one that will do that. I've dealt with Stark before and they have always been very responsible. After a big order several years back (around 20 trees) they called me a year later to see how the trees were doing and sent replacements for the two trees that had died, plus a free bonus peach tree. I hate to say anything bad about Stark after that but I was a little disappointed that e-mail wasn't sent a day or two before.
