OK, the data for all the summits is held in the database (www.sotadata.org.uk) and all the other websites query the database for the information to display.
The summits pages have only ever displayed data for valid summits.
So go to the database and see what it holds.
e.g. LD-002 (deliberately short ref to stop an auto link being created and people clicking it and getting nothing)
Scafell was deleted a few days after SOTA started because it’s not P150.
The database contains all the knowledge for LD-002, SOTA Database and it shows the info for the summit (height, locator etc.) and points and start/end date along with all the activation history. There is none as it was removed from the program 4 days after SOTA started.
West Cairn Hill SS-138 was in the program for longer and its database page SOTA Database shows not only the summit info but all the activation history.
Everything… EVERYTHING we know about a summit is in the database. But only the database web site shows info about deleted summits. AFAIK all the other sites will not show info about deleted summits although SOTL.as will show deleted summits you have activated on its map ( I thinkyou have to tell it to do that).
Maybe you could explain what you are trying to do so that help can guide you specifically ?