Responding to Rob Hamilton's request about saving his loquat tree, I had
a similar thing happen to one of my best maple sap producing maple trees.
It had three main top branches. A storm broke one off and the remaining two
were split apart 6' down the trunk. I winched the two together as tight as
possible to close the gap between them. Then I wrapped a 3/8" steel cable
around the two securing the ends with (two) cable clamps. Wherever there
was a still open gap, I sprayed it full using spray foam. It worked.