The alleged incident could land the Celtic striker in more trouble with the governing body and his club.
The 23-year-old former Hibernian player has already been fined by Celtic and faces SFA disciplinary charges after he was filmed singing about Hearts' financial strife in a bar before the recent Edinburgh derby.
Speaking last week, Celtic manager Neil Lennon, who signed Griffiths from Wolves in January, said: "I don't want him doing any more - otherwise his career at Celtic won't be as long as he maybe wants it to be."
Griffiths was originally charged with a breach of disciplinary rule 86, which covers 'not acting in the best interests of Association Football'.
The SFA could issue a second charge or re-issue the original charge taking into account the new footage which would make it a more serious matter.