I did however receive a charge certificate on December 23rd. I am waiting for them to register the charge with TEC so that I can appeal it.
What makes you think you could submit a statutory declaration/witness statement anyway?
As you received a PCN/NTO, then if you made formal reps and received a response your only route was to appeal to the adjudicator, nothing to do with TEC. However, if you made formal reps to the authority but did not receive a response then you would have grounds to make a submission to TEC.
While we're waiting, pl fill in the background and post whatever docs you have.