I was able to get this firmware to install by using version downloaded directly from the Dell website after inputting one of my service tags. There is a subtle difference in the way the two files are named, and I am wondering if the Catalog version is incorrect:
Catalog File: Network_Firmware_P32M4_WN32_7.6.15.EXE
Dell Website File: Network_Firmware_P32M4_WN64_7.6.15.EXE
All Server 2008 R2, and Server 2012 installs are 64-bit by default, so I'm assuming the Catalog version being 32-bit isn't installing on 64-bit servers.