Trigger.get()'s parameter only_true isn't really logical.
One would assume that only_true means what it says.. grab only the triggers that are true.
Instead, and as document, this pulls triggers that are true and have recently been true.
only_true string Triggers in state PROBLEM and recently switched (30 min)
I would propose to change class.ctrigger.php lines 516-518 from:
$sql_parts['where']['ot'] = '((t.value='.TRIGGER_VALUE_TRUE.')'.
' OR '.
'((t.value='.TRIGGER_VALUE_FALSE.') AND (t.lastchange>'.(time() - TRIGGER_FALSE_PERIOD).')))';
$sql_parts['where']['ot'] = 't.value='.TRIGGER_VALUE_TRUE.'";