Looks OK, I can't see any miswiring.
One thing though, the flash is fitted and the MISO is common to both the flash and the radio. If the flash chip select is not high it could be trying to overdrive the radio MISO. If this is happening it would be dependent on what the state of the chip selects and MISOs are, both awake and asleep.
Could you check that pin D8 (PB0) is driven high permanently, even when asleep. That will eliminate the flash from overdriving anything.
Mark.
Edit: I'm not sure how the software is configured, but it might have a #define for whether the flash chip is fitted or not. If it's set to not fitted it might assume it's OK to either leave D8 floating (which is actually bad anyway as the flash chip might see it as low if it's fitted and could cause excessive current consumption if it's not), or drive it low. A simple fix might be to set that #define to flash fitted, that may well enable the D8 output and drive it high for you.