No, his blood type didn't match Brantly's.
Someone said that Brantly is a universal donor.
Regarding blood types and plasma donations: The donors are opposite of what we know about red cell donors.
Group O blood type can only donate their plasma to another group O - because it has naturally occurring anti-A and Anti-B red cell antibodies.
Group AB blood type is a universal plasma donor because their plasma does not have anti-A and anti-B red cell antibodies.
Group A blood type can donate plasma to group A and group O blood types only. That is because their plasma contains naturally occurring anti-B red cell antibodies [so no one with group B or group AB can receive plasma from a group A - or a group O donor]
Group B blood type can donate plasma to group B and group O blood types only. That is because their plasma contains naturally occurring anti-A red cell antibodies [so no one with group A or group AB can receive plasma from a group B - or group O donor].
Hope that explains it a bit.