I have quite a few seeds of this cacti, and I'm interested in Mescaline. However I can't seem to get the seed to germinate even in cactus-specific soil with a daily misting. Am I missing a technique to get them sprout?

ok lontana, then you should consider that growing from seed needs a lot of patience, specially because you will only harvest in 3-5 years depending on your conditions.with that understood my sugestions are:
1-get good seeds (that might be the reason yours are not germinating)
a seller i trust in europe is khores kakteen
2-t. peruvianus grows faster.then bridg. and then panach.
3-plant 200 to get 100-150. Its nice to germinate a lot of pants not only because of the obvious but because you will get more genotypes( i think thats cool)
4-a tech. that works for me is to spread all the seeds on top of soil with out even sowing, you can powderize a thin (1mm-2mm) earth layer on top also but remember seeds need light to germinate.i like to use a container with a lid . like a tupperware to conserve humidity.make some holes in it (bottom) water the soil abundantly one day before placing seeds, put the lid and forget about misting or watering for a while. after some weeks you can start openning the lid for some hours and misting dayly.
5-expect 2-4 weeks for sprouting.
6-the first 6 months are very important for the plants because they are very fragile and wont survive with full strenghth sun and poor watering.what i do is grow them under artificial the first year and when they are about 5-10 cms high gradually put them under the sun.i use cfl bulbs, for germinating 20-50w (first couple of months) very close to the plants and then i use a 250w beast.
7-its basic not to overwater, after the first 3 months let the soil dry before doing it.
your patience will be rewarded!!!
http://www.plot55.com/growing/trichocereus.html
http://www.sacredcactus.com/

At the risk of a post where i don't say much, i have to say great advice! thanks!