clear and convincing evidence is the highest standard proving the bona fide of the marriage. Proof is irrelevant to ur current spouse.
Proof is for the previous marriage. --> in the following three years after u got the LPR, ur assets, bills or any evidence indicating that you two lived as a couple.
USCIS denies many petitions under this standard.
U may need to talk to a lawyer who's good at marriage GC