Article says could be related to past injury, the worry they have:
"It’s important to note that Morris’ neck injury wasn’t his first. In January 2019, while playing for the Washington Wizards, Morris was ruled out for six weeks following a bout of neck and upper back stiffness that led to him being diagnosed with
transient cervical neurapraxia.
According to sportsmedtoday.com, servical cord neurapraxia (CCN), “is a rare but dangerous cervical spine (neck) injury. TQ is usually caused by cervical spinal cord trauma, which can occur after a neck hyperextension or hyperflexion injury with possible axial loading (pressure applied to the top of the head). The incidence is approximately 0.2-2 per 100,000 athletes.”
https://www.miamiherald.com/sports/nba/miami-heat/article258087033.html#storylink=cpy