Ken,
The other working instance is identical set up as this - just different servers hosted by hostgator. Both use c-panal. Both have the php configuration plug in. Both were initial installations with moodle 2.5. Last week, with tech support assistance of Hostgator, I used the php configuration plug (the topic of the link you just shared) to change the version of the php to 5.5. it worked. Then I upgraded moodle and that worked.
Now I'm doing the exact same thing, and there is this discrepancy. What is interesting is that the site I am working on now IS running php 5.5. (we checked that yesterday with hostgator). It's just that the moodle 2.5 install doesn't read it as such. Not sure if it's a moodle issue either....hostgator said that if i upgrade and there is an issue, they will work on it.
And yes, I already have backed up everything.
Onward and upward.