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The issue was due to a implicit type conversion in the Ultimaker firmware.
My write up can be found at https://ansonliu.com/2024/03/ultimaker-gcode-footprint-halt/
Thanks to https://github.com/Ultimaker/Cura/issues/18319, it seems like I forgot to set the horizontal expansion for the second extruder to 0 as well.
The drawback of this method is that you can no longer compensate for elephant's foot that only affects the exterior edges of a print due to the horizontal expansion affecting each part and not taking into account inner interlocking objects' edges that are within a close threshold (e.g. 0.001mm) of each other.