Both incidents were picked up by citing commissioner Steve Hinds, who referred them to IRB judicialofficer Alan Hudson in the 12-hour post-match window.
New Zealand judicialofficer Peter Hobbs ruled on the incident and after reviewing video footage, he deemed the offence was at the low end of seriousness.
The judicialofficer who dealt with Burger's case, Alan Hudson, cleared him of the specific charge of eye-gouging as determined by the International Rugby Board, but found him guilty of committing an act contrary to good sportsmanship.
"As a judicialofficer, he must surely know that a letter allegedly written by alleged supporters of our candidates would have no evidentiary value and no court would admit it into evidence, " Mr Mbiuki said, in a statement.