Can my opponent and I decide on a victory condition to avoid a draw?
Bribery and Collusion do not really factor into this.  If there is no agreement (or offer) to exchange something of value for a particular match result, there is no bribery.  "Collusion" is not inherently illegal in the absence of bribery (No rule says I can't concede to my friends because they're my friends.)

You are running afoul of 'Unsporting Conduct - Improperly Determining a Winner'.  Entering into (or offering) an agreement with your opponent to choose the winner of the match by any means not included in the rules of the game is a disqualification.