A very interesting question.
The Encyclopedia Talmudit (Encyclopedia of the Talmud) under its section
on Chalav (Milk) records the permissibility of a person drinking human
milk - you need to read the section in order to understand in what
manner this can and cannot be done. Anyhow, it is kosher. And Parev
(neither meaty nor milky).
Whether or not blood is kosher I would have thought that the latkes were
kosher because of the relevant law of batel be'shishim (neutralised as
less than a sixtieth). I quote from Yechiel Galas, "Insight into
Halachah", about the accidental adding of a treifa ingredient to kosher
"a treifa (non-permissible) ingredient becomes neutralised by the bulk of
the mixture if the bulk is more than 60 times the quantity of the treifa
ingredient. This rule does not apply if the treifa ingredient was
neutralised deliberately. In particular, it does not apply if the
ingredient is a binding agent because it is then too important an item
to become ignored (davar hama'amid eino batel)."
I expect the blood was less than a 60th of the latka, was added
unintentionally, could not be detected in the latka. So I expect it
would be kasher.
Nevertheless, a rabbi should be consulted for a definitve decision.