I doubt things when presented with tangible evidence.

Seems like an odd thing to make up. Could be a number of factors, such as incompetence. One would assume they would want to sell this service as amazing so I don't see an angle for a psyop.

Looks like these things are 3d printed, so it's possible that the machine could have been defective.

https://www.exitinternational.net/sarco/faqs/

Either way, it's inconsequential to me really, lie or not.