Hello @MikeStrom,
I recommend you to refer to the STM32U5A datasheet and precisely Table 27. STM32U5Axxx pin/ball definitions and check whether you are able to map all OCTOSPIM signals to port G or not??
For example, OCTOSPIM_P1_CLK signal is not available on port G.
Also you can used search method to find the availability of signal on different pins as shown in the below figure

I hope this help you.
Thank you.
Kaouthar
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