Your pictures have been made available to the developers on github here: Cursor and hand too small - making work extremely difficult. · Issue #3144 · audacity/audacity · GitHub
(I am assuming you have a HiDPI screen.)
If changes affecting screen resolution were made by a windows update or started when you added the new display, perhaps those changes can be rolled back.
And you said you and your tech have tried all the tricks posted here: Curser too small
Perhaps the developers have some tricks up their sleeves…