Returning a Column Header based on max values in a row, that update when values change

Decided on registering here as all the experts seem the most helpful compared to many other sites I have visited.
I'm fairly new to excel and learning along the way and decided on sprucing up my Soccer Tipping sheet with lots of goodies.
Most of what is in here was finding similar problems and applying them as best as I could.

The issue I am having is on the Sheet named "DATA" in columns CO to DI
Basically, based on each persons current tipping percentage of each team (Found in sheet named "Tip %") I'm trying to get a column that will tell me who is most likely to pick the correct tip for each game.
I found a few similar problems and applied it to my columns CO and CZ and I was pretty sure that it was all working fine.
For the CO column it checks the % values in columns CP to CS (automatically generated and updated from Sheet "Tip %") and returns the Initial of the Person (CP$2:CS$2) most likely to tip the game.
In the case of a tie for the max value in the row, there is more data in columns CU to CX (everytime there was a previous tie for the max % and the correct tip was made, a point is scored. This is totaled all the way at the bottom CU421:CX421 to act as a tiebreaker)
Likewise for CZ but just based on a similar type of array in columns DA:DD and DF:DI being the tiebreaker

I was sure it was all working correctly but as seen in CO33 and CZ5 among many others it is not working correctly.
I apologize for the complexity of my book and if it is too confusing I understand as it is giving ME, migraines now trying to work out where I have gone wrong.
The only thing I can think of is that it is not updating when the % values change as each new round is completed. But when I "pretend" to edit the formula and then apply again using Ctrl Shift Enter it still doesn't give the right outcome, so maybe that is not the problem.

Thanks for any help or pointing in the right direction you can provide.

Regards, David.

Edit: I should also mention, whether it is important or not. The only cells that I edit is Columns G, I, K, M in sheet "TIPS" for who each person tips in a round and then Columns O and P for the goals scored in each completed round and everything else in the entire book is automatically generated/updated, which is the reason for the quite large and messy sheet "DATA"