Minecraft Middle Earth is a Minecraft community that recreates the world described by JRR Tolkien and his writings. Everyone can participate in organized events in which we collaborate to create major landmarks, terrain, caves, castles, towns, farms and more.
If you read that license link Smaug posted, you can see that you can "copy and redistribute the material in any medium or format" and "remix, transform, and build upon the material" as long as you give proper credit and a link to the license. I think that would mean you just have to write like "The texture pack is the property of the Minecraft Middle-earth server and is licensed under the <link to the license>"
So I think that means you are allowed to use the pack