Did you read the UNO manual or the ControlCenter Manual?
If you read the ControlCenter Manual you know how to install the attached ControlCenter sysex.
If you install that sysex, you can do everything you need to do in THU, and you can use it as an example of how to expand the configuration's capabilities beyond the current two Banks.
And YES, it will load THU Preset 1 when you press Pedal 6 in FCB Bank 00, and the STOMP pedals 1-5 will work in both banks.
That sysex is a tutorial. Study all of the options, which are EASY to find and understand IF you read the manual, and you'll be a Ninja FCB Master!
FWIW - your questions are not pointless. My apparent aggravation is caused by your asking me questions, then IGNORING my advice (specifically to READ THE MANUAL), then asking me more questions that are answered with pictures on the first few pages of said manual! AARGH!!!!
Seriously, you now have all the tools you need. If you have questions about the manual or something not covered in the manual. I'm (still) happy to help!
Lastly - If the attached sysex doesn't load properly - meaning it doesn't look like the attached screenshot when you upload it back to ControlCenter after installing it to the FCB, let me know, and include a screenshot. It should work fine.