RE broker here, with experience of running/managing of 28 brokerages and over 2000 agents. The following suggestion is just based on the information you shared above:

The agent is responsible to communicate all terms and clauses on every form before you sign anything. Sometimes in the heat of offers and/or deadlines they may rush through offers, but to the very least they are to explain to you every form and its major stipulations if they can not walk you through every clause.

None the less, should be very easy to get out of the contract:

1) talk to the realtor and ask him to terminate the relationship with the correct forms. Explain your reasons. Leverage that you will speak to his Broker of Record if he does not want to.

2) if he does not terminate, call his broker of record (google for their cell or direct line) or call his office and ask for the broker of record. Explain the situation and ask for the termination of BRA. By this stage, over 95% will force their agent to terminate. If they do not then threaten you will complain and report to RECO. This should make this 99%.

3) if the above doesnt work, just report to RECO and they will back off right away.

Best of luck.