I've had a glitch with the tongues, that sometimes (pretty rare) they don't drop around the body, they instead somehow drop to the far right off the map. In the area between the Grinders and the mine where you bury the bank loot, there is the house on top of a cliff that spawns the armored skags and lackeys. You can scale the cliff to the right of the map here and it will take you to a fairly level area off the map. The tounges will drop just ever so slightly past the kill zone of the map. I've tried inching forward, but as soon as the PICKUP cue pops I respawn. mashing X to grab it is ineffective.
Obviously you just kill more skags to get more tongues, but it is an interesting glitch and I'm trying to figure out why it sometimes happens. Maybe this is a dump zone? It also leads me to wonder what other loot drops may spawn in a dump zone.