It looks like MultiCursor does not directly store that information, it just implicitly stores it in the positions of the lines. I would look at `multi.vlines` and `multi.hlines`, loop over those and extract the information you need.
I'm using this code to generate subplots with multiCursor crossing plots, and
I want to get values (cursor coordinates) for all existing plots at the same
time to show them in labels (on mouse motion).
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.widgets import MultiCursor