Rough Guide to Score Attack and Dungeons

When you advance to the next floor in the dungeon, there are rare times when you get a choice between two options. If you pick the one that sounds like a noise, it apparently increases the chance of encountering Gold Hoppers. Since it was a short course, I barely made it to the 59th floor. If I get Gold Hoppers every time I have to choose, will I be able to reach the 60th floor? (Rough calculation) Also, when I chose 'Lightning Resistance Down' for the enchantment, enemies actually became weak to lightning, so it seems I didn't need to include Sharo-chan. I'll swap her out for Naruse and train her. For now, I've maxed out Aoi's HP. But this time, it's not just a score attack... The 'Otherworldly Layer EX' seems to be available until the 31st, so maybe I can do it there? Are there any reference videos?