What many of the posters are saying about the wrong grammar/ending being used is true. So long as the word was said and not skipped over, it is okay. Of course, we presume it was not intentional.
As for the idea of Ecclesia Supplet, the Church Supplying, that refers to jurisdiction in the Church ONLY. The classic example is for an excommunicated priest when asked to hear the confession of someone who is believed to be near death, he will be validly and licitly be hearing the confession and giving a valid absolution because the Church is for this time providing him with supplied jurisdiction, not ordinary jurisdiction. She cannot provide for a deficit/omission in a sacramental rite. Conceivably, of course, the Holy Ghost can, but we must go by the objective facts. The only way is for the priest to say the form over again in case of doubt.
Joe