question, did he/she seal the work? If sealed, you will have to sand it down and re start. If not sealed, I cannot imagine why it would not be, then you can experiment with a section and find out how to change it to a redder shade.
Personally, I have had some luck with playing with different shades of stain to achieve a shade from an unwanted shade, but it takes alot of experimenting. Then once you find the key, you have to make sure that the entire project is done the same way with the same amount of coats.
I would suggest that you sand down and begin over. Or you might have recourse with the stainer to re do this.