Thank you for that information Stefan. I wonder though, as there is definitely an object trapped there, likely the thing which caused the prolapse to begin with (maybe an impaction?) what will become of the situation if the prolapse is treated as per these instructions, yet the underlying cause, ie the object, is still there? Seems that unless the object itself comes out, which isn't looking like it will, then the prolapse will just turn septic and/or continue to exist as an impaction, prolonging the inevitable.
I will consider this and see how she seems for the next little while, but...