Bikester, unfortunately, there is no adapter for the forks. I would visit you LCD(Local Cannondale Dealer) (Just made that up!
)
Explain your situation to the dealer and see what he can do for you. Many times a frame will get damaged in shipping or has a warranty issue and the Cannondale Rep may have access to a spare fork with the disc tabs.
You can also try EBay!
L8R
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