I was confused with my "air" portion of my itinerary as well. I too will be flying Delta, booked as part of the package from WDW travel.
The numbers you see have nothing to do with your eticket. They are not the eticket number nor the record locator. I called WDW and the said they are etickets, and I can either show the airline ticket counter my reservation itinerary or (more likely) just use the kiosk at check-in and swipe a personal credit card for ID purposes and it will bring up my reservation and print boarding passes. The WDW lady also said she could get me the Delta record locator if I wanted.
To sum up, I wouldn't be too worried about the reservation numbers, but the 35 minute layover seems tight. It's do-able, but any delays may be a problem. Pray for good weather.