Restrict column view breaks formula for guest

I have a column called “Sales price” and my partner gets a “Partner commission” on the sales price. Partner Commission column is a formula like this: IF({Sale Fee} > 1,{Sale Fee}*60%, “”)

I don’t want to show the partner the “sales price” column, so I restrict view on that column. As soon as I restrict column view, then the “Partner Commission” column says (in my guest view), "a column named numbers6 does not exist on this board.

How can I fix this?

Thanks
Tom