Yes, we saw another post on how to disable the linux debug uart and use pin 18/19 as a “normal UART”, and it seems to be fine for our application. We will try to move forward with these pins.
For other users, in case the link from electr1 won’t work in the future: You can build the uboot-deb yourself, and need to modify one file to disable UART linux console, as explained here: How to configure the debugging serial port as a general serial port for use?.
Thanks for the quick reply.