About your thumbnail change request. We normally don't do it as it would create an enormous amount of work for us, but in your case we can make an exception.
Please send an email to firstname.lastname@example.org, add the video title and the new thumbnail you'd like on it and I will send it to our editors.
Please keep this information private as we don't want other users making the same type of request; and if possible please delete the post from the community forum.
Let me know if that works for you.