Does the Judge have the right to Sua Sponte dismiss a NISI filed by the State?

The short answer is yes, the court can enter any order, but if it runs afoul of Chapter 22, you might have a basis for a mandamus action. See Article 22.125: "The court may exonerate the defendant and his sureties, if any, from liability on the forfeiture, remit the amount of the forfeiture, or set aside the forfeiture only as expressly provided by this chapter." Usually when I point this provision out to my courts, they rethink dismissing outright without some statutory basis to support it.