This is also in the agreement: on Page 17 of the examinee guide "Exam proctors will assist you in locating your assigned seat and ensure that you have in your possession only the NCEES-designated items allowed into the exam room." So either the proctors did not read the rules either or the NCEES...
Someone posted on the NCEES facebook that they checked the 2015 rulebook and it did not mention fitness trackers. I am pretty sure it is a new rule. This would probably explain why many proctors did not know about the rule change either. One candidate even posted that at least four proctors...