Gehenna wasn’t of eternal significance. All 12 times the word occurs in the Bible, it’s in reference to the destruction of Jerusalem in the first century.
As far as the Holy Spirit is concerned, he used the word Gehenna. The Roman Catholic Church didn’t use the word “Hell” until the 16th Century. That word meant “a cover;” it’s the root of our word “helmet.” The idea of eternal conscious torment was loaded onto that word to get the Roman Catholic concept. None of this originated with me, but can be read in serious lexical scholars.
But no one’s going to make you study the subject seriously.
You won't find this troublesome word in non-Germanic Bible translations. You're going to get words in Catholic, Protestant and Orthodox Bibles like enfer (French), ad (Russian), pieklo (Polish). In the 16th century Catholics would most likely be reading it in Latin, where the place or state-of-being is called infernum.
Some of the medieval Rabbis said the "fiery furnace" that Abraham saw was Gehenna; in Matthew, too, "fiery furnace" is identified with the gates of Gehenna.
If you're looking for something rather more distinctively Catholic, that would be "Purgatorio," a temporary place for saints-in-waiting, where fire might or might not be the main feature. The name purgatorium (L) originally indicated a place for cleansing with medicinal herbal smoke, steam, and purging think "sauna".
Pope Innocent III, who historically committed grave crimes but repented in the end and went to Purgatory, actually (historically) came back to tell St. Lutgarda of Brabant that he was in a fiery place (no devils, though) and that it might last for centuries. Dante's Purgatorio, on the other hand, had all kinds of terraces and different stages and features, the parts closest to the summit (the Earthy Paradise) being the leafier suburbs.
So we frankly don't know much about that --- nothing in detail --- except that it would be purification, if in part terrible, still temporary; and hopeful, unlike the valley of Hinnom, fiery Gehenna, where *according to the Bible) the fire is quenched not, and the worm sleepeth not, and from which --- the rabbis say --- smoke is continually rising.