We don't really know there was a crash.
I mean, there's a whole zoo of captives below the surface (unless that's an illusion, too). The Talosians have clearly been at it for decades or centuries, luring in all sorts of starfarers. What happened to their ships? The Talosians claim they are klutzes with tech, but they can always make their slaves do their bidding. Perhaps those ships were safely landed and used in desperate repairs of Talosian infrastructure, perhaps they were crashed to prevent escape attempts or to neutralize the remaining crew once a specimen had been secured.
The Columbia may have been crashed on the surface after enough experimentation was done on the humans (leaving Vina disfigured and all males dead). Or she may have been recycled, and the "wreckage" on the surface was as much an illusion as the "camp".
Certainly I'd put zero faith on anything Vina or "Vina" says at the conclusion of the story. It's clearly just another desperate bid by the Talosians to prevent Pike from doing further damage (they apparently did destroy the elevator already, and apparently did set a phaser on self-destruct).
Vina during the episode may have existed in some form, but probably not as a disfigured old woman, because everything we see is more likely to be false than true. If the concept of securing a breeding pair is for real, then Vina may be alive - but I doubt that, as she supposedly wouldn't be able to breed any more even if captured intact. And the Talosians did capture young women as part of their most recent ploy; they simply had none available in the initial landing party, supposedly because
a) their initial manipulations weren't detailed enough or
b) they wanted to study a human first, and using sex as the lure would work better if they invited in an all-male team.
The overall likelier scheme is that Vina was long dead, and her various likenesses were used for manipulating Pike - first in hopes of making him a servant in whatever real scheme the Talosians had, then in sheer damage control.
However, perhaps there never was any SS Columbia? At least the second distress signal clearly was a "realtime" response sent by the Talosians, suggestive of them eavesdropping on the heroes' thoughts at a distance. And it's highly unlikely to have been a real radio signal, given the timing, so it's likely evidence of the power of the Talosians to manipulate their victims at that distance. So the heroes may have received both a signal inviting them in, and the false belief that an SS Columbia had indeed once existed. The events would make sense even in the context where this is the very first Talosian attempt at dealing with humans.
Timo Saloniemi