I don't think that's likely to be the problem directly:
[Expert@DallasSA]# echo mC4B/RZaG0NCn4aAaKWUqw== | xargs -n 1 echo
mC4B/RZaG0NCn4aAaKWUqw==
It doesn't get carved up into separate, smaller chunks, and no characters get substituted or trimmed. Still worth a shot, since it's easy to do, I just think the problem is elsewhere.
The directions only say to publish the SmartConsole session, but changes to administrators typically need an Install Database to take effect. Probably also worth a shot.