Don't lie

Your lawyer is correct that under marriage privilege, your hu*****and cannot be compelled to testify against you.  That means he will not say anything during trial.  

If he was called to testify during trial, he can get up and say "I invoke marriage priviledge and not answer that question.".  

THAT DOES NOT MEAN HE SHOULD LIE.  If he did what you suggests, (such as telling a different version of the story), he might be charged with making false police report or perjury.