I would also consider laying a layer of just topsoil over the manure mix so the rhizomes don't sit directly on the manure mix. Just to decrease any chance of rotting.
Found this article about Alpaca - it appears it doesn't need aging:
http://www.gardeningknowhow.co...
Be careful with the nitrogen content though. Since it says Alpaca manure as a fair bit, it would a good idea to not add any other nitrogen amendments to the soil or you will get lots of leaves and not as much bloom.
