Yes, it seems that the dream Pilate's wife had was of divine origin. The question is: did God want Pilate to release Jesus?
I think that this was not the purpose of the dream, because Jesus had known for a long time that that day would come. In fact, three days before he had said this to some of Herod's envoys:
Luc. 13:32 (...) Go and tell that fox, ‘Look! I am casting out demons and healing people today and tomorrow, and on the third day I will be finished.'33 Nevertheless, I must go on today, tomorrow, and the following day, because it cannot be that a prophet should be put to death outside of Jerusalem.
It is more likely that God's intention was to create resistance in Pilate, so that he would insist on the Jews, which would make them more or less guilty of the killing that was to come. Several times Pilate tried to free Jesus, until this happened:
Matt. 27:24 Seeing that it did no good but, rather, an uproar was arising, Pilate took water and washed his hands before the crowd, saying: “I am innocent of the blood of this man. You yourselves must see to it.” 25 At that all the people said in answer: “Let his blood come upon us and upon our children.” 26 Then he released Bar·abʹbas to them, but he had Jesus whipped and handed him over to be executed on the stake.