My good friend PJ has moved on to better himself. Until a suitable replacement can be found I will try to fill in.
The loose wire concerns me mostly because the clutch demands all safety interlock to be working in order for it to work. Double checking your repair job making sure it is correct, the next thing I would check is a fuse. Because of the loose wire and deck failure happened at the same time I would not assume the clutch failed. Do you have power going to the clutch when the PTO switch is turned on? If not I would work backwards to find the open. If you do have power to the clutch, well your fears of a bad clutch might have come true.