Note that the Neos derailleur is only on the D7 bikes. The 8 and 9 speed models have more conventional SRAM derailleurs this year, Shimano in the past.

Theoretically, an adapter claw, like the one near the bottom of this page, might be used to mount any rear derailleur. The bolt is supposed to fit through the back of the axle slot without the need to drill an extra hole. However, I seriously doubt whether this would work on one of the D7 bikes, and I'm not recommending it. From the picture on this page, it looks like the axle slot might be too short.