The names are wrong. The bullpup is the Ash-12 and the other is called MG36.
The Ash-12 is in the tags. The other one is a strange hybrid with some fictionalized bits, which can be converted in Modern Warfare's gunsmith to the G36, G36C, G36KA4, or even the MG36. That one's up for debate, but the names are just going off of what they're called in Modern Warfare. The Oden and the Holger-26 respectively.