I think your fears would be unfounded because CM has no one out there to enlist for anything like that from prison, IMO.This is one reason why I have real fears of being a juror in a serious case like this.
There have been multiple examples in the past where a defendant will enlist some outside help to threaten or harm a juror or other members of either the Prosecution or Defense.
It is rare thankfully but it can happen and I think its a valid fear to have. How easy would it be for him to enlist someone to take out a juror in an attempt to get a mistrial.