2005 Dodge Caravan Loss of Coolant

2005 Dodge Caravan 6 cyl Automatic 170000 miles

I was leasing this vehicle for work and two weeks after I had gotten it, the van died on me. I took it back to the place where I had gotten it from and they said that the coolant dried up which resulted in having to replace the engine. The company that I leased the van from supposedly made sure that all fluids were in at levels they were supposed to be prior to leasing me the van. My question is, if there was coolant in the van, what would make it dry up in two weeks?