Haven't tried AWS ... but do have one on Goolge Compute Engine ... similar?
Interesting ... the directions, if you followed verbatim, appears to be a minimal CentOS flavor, but not mentioned is the version (probably a 'special' as per AWS). The directions appear to be for 6.x version of CentOS.
For the Moodle piece, since you do have ssh:
which also has info on cron.
'spirit of sharing', Ken