With over 40 years in the elevator industry, I always shudder when I see kids ‘playing’ on/with an escalator, especially with clueless parents right there.
Even with all the safety devices in the latest codes, they are still meat slicers..
And as to this incident, I’d need to know where the ship was built and under whose code the elevator was installed to even make an educated guess beyond the most obvious - no lock out-tag out, and failure to push/flip any safety switches (aka stop buttons). Many countries have very lax safety codes for their vertical transportation devices.