"I can confirm the club is monitoring the situation, also via the player's agent, and we're waiting for the decision," Mr Mussini said.
Mr Mussini also praised Zebre's newest player as a "great champion" on Facebook on August 28.
Muliaina's manager Simon Porter could not be immediately reached for comment.
At the time of his arrest, Mr Porter said the former All Black was "pretty upset" and "shocked" about the allegations.
Muliaina, 35, was charged with sexual assault in July after an alleged attack on March 7.
The day before the alleged incident, Muliaina appeared for Connacht as they lost 18-17 to the Cardiff Blues.
He was arrested in April at the end of Connacht's defeat in the European Challenge Cup quarter-final, with TV cameras capturing the moment he was take away by police.
Yesterday, Muliaina stood calmly in the dock wearing a smart dark suit with a shirt and tie as the court heard that there was CCTV footage of the alleged attack.
Muliaina's legal team said he would be "contesting the charges" and a trial date was fixed for February next year.
Judge Eleri Rees gave Muliaina unconditional bail ahead of his next court appearance in October.
Muliaina, a married father, was one of the All Blacks' most popular players and was appointed captain for the opening tests of the 2009 season.
He became the second player to earn his 100th cap for the All Blacks in the Rugby World Cup quarterfinal in 2011 and retired from international rugby in the same year. He had previously played for the Blues and Chiefs.
The Samoan-born fullback and his estranged wife Hayley have a 6-year-old son, Max. He was recently in New Zealand for Jerry Collins' funeral in Porirua.
His lawyer has previously said the rugby player "totally denied the allegation".
- Additional reporting from the Wales News Service
