Both USB_INSIZE and USB_OUTSIZE can only be 8,16,32 or 64.
If you want to send 10-bytes per report, it needs to be 16.

Question 2, I don't understand.
If you have them in arrays, just copy them to the USBTXBuffer.

And what looks like "garbage data" is the analog reading from the pots being sent periodically.
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