Question about Ivanus Enkomi's auxiliary grenade launcher

[Guy]

I can't find anything in the SM Codex regarding the auxiliary grenade launcher, which according to Forgeworld's Badab character pdf (http://www.forgeworld.co.uk/Downloads/Product/PDF/B/badabupdate-v2.pdf - Enkomi is on the last page) the Minotaurs chaplain Ivanus Enkomi comes equipped with.

The closest I can find in the Codex is the Astartes grenade launcher. I'm very new to the game, so I'm wondering if I substitute the rules for the Astartes GL for the presumably now-defunct Auxiliary GL? If so, why would I pay an extra 10 points for the Crozius Arkanos when all I'm really getting for those points is a seemingly less effective GL, losing the +2S granted by a regular crozius and gaining Master Crafted.

I'd be really grateful for any advice, sorry if I'm missing something obvious.

[Vindur]

The auxiliary grenade launcher is a piece of equipment from an older addition of the space marine book. It was taken in addition to other weapons and didn't take a hand/weapon slot.
Not sure of the profile as I do not have the book anymore.

[Blood Shadow]

The Auxillary Grenade Launcher appeared in the 5th Ed C:SM

It is a rare item that can fire in addition to another weapon in the shooting phase, chose which grenade

Frag: 12" 3 6 Assault1, blast
Krak: 12" 6 4 Assault1

[Mr.Pickelz]

Check the Badab War books, the Minotaur chapter's characters are in those two books. Their wargear rules would be with them as well.

Edit: Here is the link to the Forgeworld page of the two models. It says "Rules for these special characters can be found in Imperial Armour Volume 10: The Badab War Part 2"
http://www.forgeworld.co.uk/Warhammer-40000/Space_Marines/Space_Marine-Infantry-and-Accessories/ASTERION_MOLOC_AND_IVANUS_ENKOMI_OF_THE_MINOTAURS. html

My guess is that their wargear (like the grenade launcher) would be with them, or mixed into the weapon profile index.

[Guy]

Thanks man, that's really helpful. I'll use this information to begin with unless someone more knowledgeable at my local store says otherwise.