Everything is very normal in the Bonus Round of Deltarune's third chapter, and you should absolutely trust Mr. Tenna, no questions asked. Below, you'll find IGN's guide to the Bonus Round in Deltarune ...
After playing through Round One of Deltarune's third chapter, you'll end up in the Green Room for the first time. Similar to the backstage area from the Dark World portion, you'll be able to speak to ...