Falsification of public documents and annulment of marriage

Good evening attorneys,
Would like to seek advice regarding my case. I am my husband's second wife. My husband's first wife (through her lawyer) falsified their nullity of marriage which she obtained in Cagayan. This certification is submitted at NSO and has been annotated in their marriage certificate.
My marriage with my husband has not been that great as he was irresponsible and cheating. My last conversation with him was that he plans to file an annulment immediately. After that, we have not talked and i have not received monetary support for our son.

Despite having the annotations in their NSO marriage certificate, is our marriage invalid?
If the annulment pushes through, will we both be liable for bigamy since I knew of his first marriage and that the wife falsified the documents? Will there be another case for the wife who have falsified those documents?

Hoping for your advise. Thank you so much!

If the  annulment was in fact falsified, your marriage is void (not valid from the very beginning). You may file a petition for declaration of nullity of your marriage, but the fact that the annulment of the first marriage was fake must be established first.

The wife may be held liable for falsification of public documents and another crime for use of falsified public documents since she had it recorded in the NSO/PSA.

Hello attorney, thank you for your reply. Very much appreciate it.