I finally got some answers about cakes and deliveries. Herbrokemom is so correct - do not send anything via UPS or FedEx ONLY USPS. Those items sent that are not deliverable within 2 days are sent to the distribution center outside of town and it's quite a car ride to pick them up. After 7 days they are returned to sender.
As to cakes, UDel is still offering cake/giant cookies - here's the link https://www.mis2.udel.edu/Dining/bakeshop/index.html
Along with that, SAS does deliver (in person) to the dorms for a $2 charge - they need 24hrs notice.
My son's RA was so helpful and even offered to pick up a cake or balloons anywhere in town and deliver them himself!