I looked over the summary. Under consent for adoption, I do not see any indication that consent by the grandparents is required. You do need to speak to an attorney. I would presume that if the biodad's right have already been terminated, that they are no longer LEGALLY the grandparents.
Texas Adoption Statute Summary
Texas Code Annotated Family Code Sections 162.001 to 162.025 (1997); 15.01 to 15.07; and 11.03 to 11.04 (1997)
Who Can Adopt?
Any adult may adopt. A husband and wife must adopt jointly, including the spouse of a stepparent.
Who Can Be Adopted?
Any child or adult living in the State may be adopted.
Consent to Adoption
The written consent of the following people must be given:
1. both natural parents;
2. a managing conservator (a person or agency who retains all of the rights, privileges, duties, and powers of a parent to the exclusion of other parents) if one has been appointed; and
3. the adoptee who is 12 years of age or older, unless waived by the court.
Consent is not required of the following:
1. a parent who has voluntarily left the child alone or in the possession of another with no intent to return and without providing adequate support for the child;
2. a parent who has abandoned the child without means of identification; or
3. the alleged father, who upon notice fails to respond by timely filing an admission of paternity.
No decree for adoption may be filed unless parental rights have been terminated as to each parent of the child. Consent to the adoption may be revoked any time before the final adoption order is entered.
Putative Father Registry
A putative father who files notice with the putative father registry is entitled to notice of adoption proceedings.
Confidentiality
The preadoption report shall provide adoptive parents with the health, social, educational, and genetic history of the child, which shall include nonidentifying information about the child's biological family.
A mutual consent voluntary adoption registry shall be established through which adoptees, birth parents, and biological parents or siblings over 21 years old can locate each other. If both parties have agreed to disclose information then a match will be made and identifying information will be released. In certain circumstances, such as where the parent has failed to respond to requests for the parent's consent or is deceased the identifying information will be released.
Permissible Fees
There are no provisions in the law regarding permissible fees.
Place of Adoption Hearing
An adoption hearing may take place in the court of the county where the child or where the adoptive parents live.
Authority To Place Child
The Texas Department of Social Services or an authorized agency, person, or entity may place the child for adoption.
Relative Adoption
In the case of relative or stepparent adoption the preadoption report on the child's health, genetic, social, and educational status is not required.
Re-printed with permission from the National Adoption Information Clearinghou