Join Date: Aug 2011
Location: Barcelona, London, on a plane
Programs: IB+ Gold, TK E+, Hyatt Globalist, Marriott LTP, IHG Diamond
Posts: 14,182
Don't overthink it. The most likely outcome for what you describe is that Hyatt keeps your points and the hotel double-charges you the cash amount on top.
If you want to switch from points to cash, do it before the cancellation deadline on your points booking.