I too see the websites that claim they rescue plants from construction
sites. I'd like to see permits to that effect. Conservation groups
can get permits, but not easily. I am very suspicious about commercial
sales of endangered plants collected in the wild.

The North American natives are a problem in another respect. They are
notorious for not showing above ground for years at a time (kind of
like cicadas). In deep woods that may not matter, but in a garden it
does. Is your mom likely to remember the plant is there and protect
a bare spot for it, for years?

Instead of this highly finicky orchid, how about a hardy cyclamen?

Una