On the issue that a judge can undermine the status of a bench by one of his actions.
First of all it is not easy to do this. Outside the bench the CJ of the SC is watching everything. CJ has the powers to refer any judge to Supreme Judicial Council.
A judge cannot excuse himself from the bench either. There has to be a SOLID reason (health issue etc.).
A judge can write a note of dissent, note of addition and may even disagree with his fellow judges.
Dissent and Addition are easy and not likely to be frowned upon or challenged.
Disagreeing is very difficult and there has to be a very solid legal / constitutional reason to do that. This is a constitutional court and the admissibility / maintainability of the application has been agreed already - even by Shareef's lawyers. Finding a constitutional reason to disagree will be difficult if not impossible.
Also, the judge who leads the bench (in this case
@Farah Sohail favourite - justice Kohsa
) has enormous influence on the outcome of the case. He can bring out a unanimous verdict.