When the bride is kidnapped the groom finds the engagement ring left on the dressing table, but when the bride is rescued she's wearing the ring without having seen the groom again yet.
Drying the business cards in a toaster would have just burnt them. She should have put them on a cookie sheet in the oven.
If Carnegie thought the business card case had something to do with Nikki's car crashing she should not have kept touching it without gloves on, and she shouldn't have had her friend touch it, either.