md5sum will verify the integrity of the stage area directory but not the integrity of the CDs/DVDs.
To check the contents of the Media Pack, try to view the contents of the DVD itself (use ls command).
If downloading files from https://edelivery.oracle.com/ website is not an option for you then you may need to log a SR and ask Oracle support to send you another Media Pack.
Looks like a media corruption.
Just try to download this software pack from e delivery and put it onto your staging directory or burn it onto a DVD, then use the md5sum on the staging directory to check the integrity of all the files. Probably this will save some time in ordering and shipping the media pack.