Going strictly by Canon won't help here. Roddenberry himself once said  the machine planet was the Borg homeworld, he could be joking or not, ymmv.
But the concept is intriguing. I read some not-half-bad fanfic theorizing the machines were in contact with V'ger until the fusion with Decker -- when they lost contact they were intrigued by the disappearance and assimilated their first organic species -- until then they didnt do that-- trying to understand whet Vger had done with the human(s) - thus inventing and eventually becoming the Borg as we know it.
What's in your "personal canon", if such a thing exists?