Full credit to Skuller 101 on true achievements. I followed his guide to complete it myself
To start the Epsilon Program missions you have to play as Michael, go to your phone, open web browser and search for EPSILON,
enter www.epsilonprogram.com, scroll down to "EVALUATE YOUR IDENTITY", finish the short test and go back to your map.
A new secret mission should appear on your map to the north, go there and walk up to the the red truck.
After that you will get abducted and receive an email from Marnie to visit the Epsilon website to donate $500.
A short while after donating a new mission will appear on the map, during the "mission" you will meet Marnie, after the meeting is over she will ask you to visit the Epsilon website and donate $5000 to proceed.
Wait another short while and eventually a new icon will appear to meet Marnie. After the meeting you will be tasked to find 5 vehicles:
- Pegassi Vacca** $123,000**
- Benefactor Surano** $154,000**
- Declasse Tornado (can be found driving around Vinewood)
- Enus Super Diamond** $250,000**
- Dinka Double-T (bike can found outside the LifeInvader offices for an easy find)
**website listed prices**
**can be found online ingame on your phone by going to the travel and transport tab and scrolling down to southernsanandreassuperautos.com**
UPDATE 1:
Big Thank You to A 0 E Monkey and llDurbinll for info leading to the making of this map for the different car locations
After delivering the cars you meet up with Marnie again and are tasked with finding extraterrestrial artifacts in the desert using a scanner.
*** Spoiler - click to reveal ***The first "artifact" you find is an old television set, the second "artifact" you find is an old car battery and the final "artifact" you find is a shoe.
After another short while you will receive an email from Marnie to donate $10,000 to proceed.
After waiting even longer (man it's a lot of waiting) a mission will appear and Marnie will task you to buy and wear the official robes from the website (it costs $25,000, takes 24 hrs to show up and you have to leave the house for them to deliver to your closet) for 10 days (you can go to your house and keep sleeping until the 10 days are up)
After you are done sleeping the 10 days you will receive a text from Brother Brother Cris saying they will summon you soon.
After finishing the run and waiting for another short while a mission will appear and you are tasked with running around the desert CONSECUTIVELY (which means you have to run around IN the Desert or the counter will reset if you leave) for 5 miles while wearing the robes
It took me about 5 minutes of just running in a circle
After your pilgrimage is done you meet up with the leader of the cult and you have 3 options:
1. To give them the $50,000 but you don't have to fight anyone and receive an old tractor
2. To just drive away without going to the meetup site and receive the $2.1 million
3. To go to the meetup site and steal the $2.1 million but you end up fighting your way out past security but you receive a gold medal for killing everyone