Thank you for the example dataset.
I could reproduce the error, but I don't know if the problem is coming from Brainstorm or MNE.
I posted the question on the MNE-Python user forum, together with the first 10s of the recordings you shared (the file contains only the signals and sensor positions, no metadata at all - fully anonymized):
https://mne.discourse.group/t/calling-maxwell-filter-on-yokogawa-recordings-from-brainstorm/6452