this seems to come from leaving court while carrying people who aren't allowed in court - when you load back in court, court doesn't account for the carried player so it doesn't save it's position in management mode, and the camera gets thrown into the void trying to find a middle point between invader and glitched defender on the next battle. I shared what I could with the dev on discord but for now I'd recommend just making sure you drop people before leaving court, especially if they're not allowed in court otherwise.