Thank you for taking a few steps back and looking at the big historical picture in context. In one of the videos, Father Purdy says Santa Maria de la Buen Suceso de la Purifacion may be translated as Santa Maria of the Good EFFECT of the Purification.
The good effect, he suggests, came about on the 40th day following the Birth of Jesus, known as Candlemas, Feast of the Purification and the Presentation of Jesus in the Temple.
Our Lady did not give birth in the manner of a fallen human being, was not contaminated by blood and in an earthly sense, did not need to be purified according to Jewish law. Father Purdy suggests that when St Simeon told Our Lady "a sword will pierce your heart" this was the genesis of her Immaculate Heart. God used her perfect humility and perfect ascent to His will to purify her in this unique way.
It may be
and can be
translated as such, but the main translation will always be
Good Success. This is far beyond anyone's ability to reverse. We could reasonably conclude that this was meant to be when, according to Our Lady's wishes, the prophecies were made known to the English-speaking world of the 20th century it was as Our Lady of Good Success. Fait accompli.
Furthermore, "Good Success" has also been used for hundreds of years already to translate the same title in Madrid. The title Our Lady chose for herself in Spanish would prove the be difficult to translate into English precisely. "Good Event" or Fr. Purdy's "Good Effect" is simply not used at all in common English, and they're both really awkward. Off the top of my head, even when you try to create something that makes more sense as an English phrase such as "Positive Effect", "To Good Effect" or "Happy Occasion", it totally misses the mark as well. We should take a cue from Our Lady and let false friends be fast friends instead: the Spanish describes the actual event, the English describes it's broader consequence.
Interesting take on the Immaculate Heart, though I think it safer to say her heart was always immaculate. Rather, the Presentation/Purification was the beginning of Our Lady of Sorrows while at the same time remaining one of her joyful mysteries. A double feast, a double mystery, two Hearts, and two languages covering a double aspect on the second day of the second month of the year. Works for me!