Is a Self-destructing “Delete on Read/View” message deleted immediately after the message is read?

Actually, there is a short delay after that.
A “Delete on Read/View” message is actually deleted about 10 seconds after the recipient reads the message; nevertheless, it cannot be re-sent or forwarded in that time. This allows their device to properly close the message and clear the screen before a confirmed deletion takes place.
Therefore, as CoverMe is used to send messages, there’s no necessity to worry about your online security or to worry that your message will possibly be abused.