The interview isn't meant to provide due process. As many people in this particular thread will attest, many VOs will use intimidation, insults, groundless accusations, misinterpretation, and various techniques to perhaps justify the decision that they've already made in their minds before the interview. Some have suggested that this is to throw you off balance, so that you would reveal some tidbid of information that could be used against you. In the end, it's an opportunity for you to change the VO's mind.
That you say you will re-apply and address their concerns, tells me that there were still doubts in the VO's mind that you were not able to satisfactorily address in the interview. Since they don't tell you in advance what their concerns are, it is difficult to prepare evidence in advance to address those concerns.
You should be able to expect due process at the full hearing, however. It is in a court setting, with a judge and counsel, with set procedures and allows for cross-examination, witnesses, disclosure, etc. I believe that the hearings are recorded. You can have up to a full day to explain your case, and have to opportunity to appeal to federal court if you feel that there was an error in the process.
Of course, if you apply inland, there is no appeal.