Amy,
I have noticed a similar problem as reported in the OP.
The Scorm activity settings and the Moodle settings can be contradictory. While Scorm 1.2 is clear about completion and even LMS behaviour - within Moodle, it's not obvious which takes precedence or indeed whether there is any logic at all.
I generally tell my students that if there is any completion mark (red, blue, green, whatever) beside a Scorm activity then it means that they have at least opened ("browsed") it. There's no guarantee that the Moodle sign means that they have: "passed, failed, completed" the activity or their attempt is "incomplete".
This is an irritating problem but not fatal.