If you change the single quotes to double quotes, then you can use escaped characters. You should be able to use
\n to do a line break. If you are interested, you can learn more about this here.
Don’t forget to use the filter to replace the strings, so as not to have to apply your changes to the plugin on every update.
EDIT: This solution is not entirely correct. Please stand by and I will give you a full example of how to do this shortly.