I'm one of the lead developers on the Adapt Learning open source e-learning framework - following some queries from a user in our Gitter chat room about SCORM errors occurring with content built using Adapt on the Chamilo LMS, I decided to do a bit of investigation for myself using https://1.10.chamilo.org/
I uploaded some content that was SCORM wrapped but didn't actually track so that I could issue all the necessary commands myself using the developer tools.
What I found was that when you set the lesson_status to 'incomplete' then call LMSCommit to save that change, the next time you ask for the lesson_status within the same session, an empty string is returned. This is not a valid value for lesson_status.
Here's a screenshot of the developer tools showing what I did:

I also tried again in the next session - as you can see it did successfully record the 'incomplete' status - but, once again, a call to LMSCommit causes it to be 'wiped' from the API:
