What do I do if my 17 year old daughter got pregnant by 33 year old Mexican with no green card?

The big question here is whether or not the Mexican guy is still around and whether his relationship with your daughter continues. While your daughter could file a petition to establish a parental relationship if he can be located, the main reason for that would be to establish child support and some parenting time for the father if that is appropriate. As to your relationship with your daughter, if she is over age 18 and is the only parent named on the child's birth certificate, she is the only one who has custody and control of the child. The only way you could establish a legal basis for imposing contact and/or grand-parenting time with the child would be if your daughter is not caring for the child in an appropriate manner which might be the basis for a guardianship petition in the county where the child has been living since birth (if the child was over six months old, the jurisdiction would be where the child has lived for the last six months). On a more personal level, try to maintain contact with your daughter and give her whatever support you can. After all, whatever is happening right now happening for the first time in her life and that can certainly be stressful.