Hello and welcome to JustAnswer. Please note:This is general information for educational purposes only and is not legal advice. No specific course of action is proposed herein, and no attorney-client relationship or privilege is formed by speaking to an expert on this site. By continuing, you confirm that you understand and agree to these terms.
No, that first marriage is void.
1) Colorado allows cousin marriage.
2) States generally recognize marriages of first cousins married in a state where such marriages are legal. So in most cases, that other state is would have recognized the marriage as valid even if it itself did not recognize cousin marriages. Ergo, the more proper thing to end the marriage would have been to file for divorce.
3) But regardless, if a Court terminated the marriage, then it is void. It does not matter that the annulment occurred outside of Colorado. US Courts recognize each other's decisions under the Full Faith and Credit Clause of the US Constitution. The marriage is now void.
I hope this helps and clarifies. Please use the SEND or REPLY button to keep chatting, or please RATE when finished. You may always ask follow ups at no charge after rating. Kindly rate my answer as one of TOP THREE FACES/STARS and then SUBMIT, as this is how experts get credit for our time. Rating my answer the bottom two faces/stars (or failing to submit the rating) does not give me credit and reflects poorly on me, even if my answer is correct. I work very hard to formulate an informative and honest answer for you; please reciprocate my good faith with a positive rating.