Well the game is free to make up any amount of lore to justify totally changing Shelob into something she never was replete with whatever fanfic story they’ve come up with for her…but actually saying it can be supported by the written material is too ridiculous of a stretch to even consider.
For those wondering, Shelob is a spawn of Ungoliant who lives in Cirith Ungol whose most shared trait with her mother besides being a giant spider is her chronic hunger. She is independent of Sauron but Sauron sort of likens her to a pet guard dog keeping watch over one of the entrances into Mordor. She also bred the Spiders of Mirkwood.
For the record I never really needed to ‘prove’ anything. I just like talking about this stuff even if I loath the games that make a complete mess of it.