Huh. Does the file (the kernel module, I mean) actually exist on your device? (It's not in the FW package, and it should definitely not be here at all from my understanding of the kernel config...).
Stupid but obvious remark: make sure you're actually running the updated version of the script
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Other than that, some general remarks: set -xeo pipefail, curly braces, quoting, shellcheck, check FBInk's output, and given set -x: check the output, period
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