Just caught up. Great episode.
You know what I didn't get? Why didn't the Canterlot ponies recognize Twilight? The personal apprentice of the princess seems like someone they would know about. Did Celestia keep her teaching a secret?
I think Celestia maintained a certain regal distance, and while she gave Twilight the Canterlot Library and a private two-way dragon communication link to a world ruler, all anybody from Twilight's school knew about her was that she was an under-the-radar book nerd. Nobody bothered to know her well enough to realize she was Celestia's protege.
At the Gala, some high-class ponies may have wondered who was standing next to Celestia in the greeting line, but probably thought nothing of it. Just some dying pony from the make a wish foundation or something. Not a potential threat or advantage to their ladder-climbing.
The general crowd might not recognize the mane 6 from "just saved the world" medal ceremonies, because they're not household names. If they introduced themselves as heroes, they might get some "oh right, I saw that" recognition.
You'd think Twilight would be famous. Just as you would think Rainbow Dash would be famous enough after the Young Flier competition so Rarity wouldn't have to lie about her.
That was an amateur-level contest in Cloudsdale. Likely only remembered by sporting enthusiasts, and an effective but ultimately irrelevant credit to put on a Wonderbolt application form.
And even if she got into the Wonderbolts, the general public wouldn't really know her apart from other team members.
Although you're right, that Rarity didn't have to lie about who Rainbow Dash was. Rainbow Dash is a friend who knows the sport extensively. That's all she needed to say.