Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Redmond to Duesseldorf Intl Airport as you normally would.
Located just 1.8 mi from the city center, Bend/Redmond is the airport most travelers will use when flying to Duesseldorf Intl from Redmond. Booking flights from Bend/Redmond (RDM) to Duesseldorf Intl should be relatively easy as there are 0 daily outbound flights to Duesseldorf Intl from 0 different airlines.