Im not exactly a connoisseur of yuccas so i can comment extensively on them. Ive simply grown four species: gigantea/elephantipes, gloriosa, aloifolia(had a variegated one), filamentosa. If nothing else, im very familiar with those .If you need me to provide ID info, ill do it tomorrow
Another thing.. do you have a full photo of your "gloriosa"?
Something feels off about the inflorescence. It looks a bit short...
If i know anything for certain, is that gloriosa spikes average out at 70 cm(roughly 3 feet).