Mexican Temporary Residency question

Hey guys, I think I may have posted here or on another sub in the past but I didn't get a clear answer so I'm asking again.

Basically I live in the US with a green card and I got married to a Mexican citizen. I am not Mexican and he has no plans to apply for a green card due to the fact that we live near the border and we can visit each other very frequently. Also he has a well paying job in mx. After we did all the marriage paperwork in mexico, we started looking into putting our names under the beneficiary section on our life insurance and all that but he was told that for his retirement funds, the person had to have at least a temporal residency in mexico as it requires a CURP number.

So I started looking into getting the temporary residency as it seems there's no requirement on actually living in Mexico to have it (I don't want to abandon my green card) but it's unclear if submitting the information in the Mexican consulate or doing all this in mexico would raise red flags on the US side. Also, I haven't submitted paperwork on our marriage in the US as of now.

Any info on what steps we should take or recommendations you have would be helpful, thank you much.