Sounds like a bit of confusion between the meaning of a “presentation” and an “interview.” Preparing to talk 4-5 minutes without interruption is a presentation, while being asked questions is the definition of an interview (Interview - Wikipedia).
First thing you can do is read the judges guide, which can be found here: https://www.roboticseducation.org/documents/2018/09/vrc-judge-guide-2018-19.pdf/ If you want to win, you need to know what the criteria is, right? As far as interviews go, look on page 16 for “suggested questions” that a judge might ask you, and look at pages 19-20, which is the Design Award rubric. One side of the DA rubric is where your engineering notebook is scored, and the other side is where your interview will be evaluated. The items on page 20 are what the judges are using to evaluate your team.
It’s fine to have a presentation ready, but you must be prepared to go “off script” when a judge interrupts you with a question. If the presentation sounds too scripted, like students are just “reciting their lines” without knowing what they are actually talking about, you can expect the judged to derail your presentation with some questions to probe if your team is genuine or not.
When I interview a team, after greeting the team and making sure there is time for an interview, I’ll usually say “tell us about your robot and your team.” Here’s your chance to talk about anything you want, and start a prepared presentation (if you have prepared one), but as I said before, if it sounds like you’re on a tightly rehearsed script, be ready for the judges to switch to a normal Q&A interview. On the other hand, if it sounds like your teams is speaking from a well-planned outline (not a script), and you can answer the occasional question then continue on your outline (which covers the points in the rubric), your interview will probably be rated highly, even without a lot of questions being asked.
Some general advice: when we start the interview, we will have already evaluated your engineering notebook and know if you are in the running for Excellence or Design. This might affect the types of questions we ask, because we have to determine that what you wrote in the notebook is genuine. Be ready to talk about your design process and how you made decisions. Outside of the questions and answers, we’ll be watching to see if the entire team is involved, or if just one person is doing all the talking. Judges and event volunteers are everywhere, and we all talk to each other, so how your team acts outside the interview (good or bad) will get to the judge’s room. Your mentors/coaches can sink you too, with bad sportsmanship or tinkering on you bot in the pits, or doing programming for your team at the practice field. Best thing your mentors can do at competition is keep their hands in their pockets, and definitely leave the area politely when the judges come for the interview.