That stinks. They should have handled things differently.
I had a similar issue at a Toyota dealership a few years ago. I have a Highlander Hybrid that I took in for an oil change. I noticed soon after the service a slight burning of oil smell. I couldn't take it back before leaving for a two week vacation. I kept an eye on the oil and had to add two quarts of synthetic over the two week period.
When I did take it back to the dealer they said it was due to a faulty seal on the oil filter. In other words, the seal was not properly adhered to the filter itself. They were very apologetic , changed the oil, reimbursed me for the oil I added and gave me the next oil change for free.