Hi,
I think it's pretty unlikely that a lecturer would refuse to write a reference for you based on your fee status. If one of your referees is somewhere near the top of the food chain and has responsibility for budgets, that person might be a bit p'd off with you if your change in status caused a budget shortfall but even that doesn't seem very likely and is no reason for them not to write a reference. As TreeofLife says, you'll just have to ask again.