These elite soldiers are supposed to be an insurance policy that prevent the Mana Assimilatior from ever being activated.
Many of the warriors chosen to be put in stasis weren’t exactly happy with the idea of never seeing anyone from their time again, but they really didn’t have a choice.
There are 8 Cryo facilities throughout Aethra, and there were originally 16 warriors.
Steele survived to be unfrozen in 3067.
Aibel’s Cryo tank malfunctioned and defrosted hundreds of years before 3067, but Aibel survived and left the Cryo Facility, leaving only notes to Steele.