In order to successfully handle the official Raspberry Pi keyboard / hub (Holtek Semiconductor, Inc. Wired Keyboard / Genesys Logic, Inc. Hub) I had to accept a NACK as a success in HCDCheckErrorAndAction. Something like:

if (interrupts.NegativeAcknowledgement) { // Endpoint device acknowledge
sendCtrl->Success = true; // You can set the success flag
sendCtrl->GlobalTries = 0;
return ResultOK; // Return OK result
}