I thought that there was soil on the other side of the wall, like it was either a split basement, or else a full basement with poured stairs coming down into it. If that was the case and there were poured walls on the other side of the door as “bulkheads”, that would buttress the wall from leaning out, not necessarily from leaning in. We have very active soil in this area here and things like that are not uncommon.
If there isn’t soil on the other side of that long wall then I would be mistaken, but that was how I read the description.
I really think she’ll need an Engineer on-site to tell her, and if they want a building permit for the removal they’ll likely require one anyhow.