Structurally, it certainly doesn't look like any Tommasini I have ever seen. It lacks the details as you noted, and although it is nicely finished, it's not in keeping with other Tommasinis that I am familiar with. I have heard Tommasini keeps strict control over their decals, but I'm sure some have slipped through the cracks. It's possible that this is not the genuine article.
That said, Tommasini has never been shy about experimenting with different tubesets, so it's entirely possible that they made a few frames using Oria tubing as an experiment. I would write to Tommasini with photographs and ask if they have a record of such a frame being built.