Deleted old videos from our brand channel, any way to get them back?

Sorry to say it, but a deleted video on YouTube is gone for good. There's no trash folder and the platform doesn't restore them, the views and comments go with it. Your only real hope is a copy somewhere. Ask whoever edited them for project files or exports, check old laptops and shared drives, any cloud storage the team uses, and whether the videos were ever posted to other platforms (social uploads keep their own copy). Even if you find the files, a re-upload is a new video at zero views. For next time, set channel permissions so only one or two people can delete, and switch videos to private or unlisted during a cleanup instead of deleting them.