IONICUBE based systems are not compatible with the Simucube firmware; you will have to manually put the system back to DFU mode using the dip switches, and flash MMOS firmware back.
If this is an Ionicube base system he will have to reflash the discovery board.
To do this you need to plug a USB cable into the other port on the discovery board.
I would suggest reaching out to the original builder. Be very careful not to knock any of the little wires off on the discovery board as their location is critical.
Trying to help someone troubleshoot the Ionicube1x board builds was much more challenging. Especially if it was a DIY build by someine with very little mechanical and electrical knowledge.