Yes, it is generally still possible to earn a passing score if you enroll in a DEDP MicroMasters course session after its start date—although the DEDP MicroMasters team generally does not recommend enrolling in a DEDP MicroMasters course more than a few weeks after the start date of a course session.
Each week of DEDP coursework builds on material covered in previous weeks, so learners joining the course session after the start date will have to catch up to the current week's content, which may be challenging. Learners with relevant background knowledge and prior experience in the topic area of the course may find it easier to catch up, but it is not guaranteed—especially the longer after its start date you join a session.
Because assignment deadlines are strict, you cannot submit assignments for credit after their due date for any reason. This includes late enrollment—if you enroll in a course session after one or more assignments are due, you will not be able to earn course score for those missed assignments. DEDP courses do, however, drop one or more of the lowest-scoring pieces of coursework, which do not count towards the Cumulative Course Score.