Legal Question in Family Law in Texas

I would take it to the Judge and see if the Judge will accept it.

Now all a notary does is sign and show when their notary expires - the State of Texas no longer uses a "seal". So if the Waiver of Service is signed and dated by a notary, the judge will probably accept it.

Yes. The Waiver of Service is only required to be signed by the other party and notarized. An apostille is not required - these are generally used only for authentication of official state documents, like birth certificates, marriage licenses, etc. for use overseas.