Solve problem with Mining Pool

We have developed a Pool for HyperCash Blake (14r) algorithm that it is running but with errors. The issue is that miners in HyperCash mining mode does not respect/use nonce value in block header. This is miner unique value set by pool, therefor miners are creating same blocks with same hashes at a same time. There is probably some trick how to make miner accept that value. I am looking for someone with experience on blockchain Decreed Coin or HyperCash Coin for guiding us solving the problem.