Problem #1
Symptom:
The submit score button is not displayed to the student.
Cause:
"labsim_allow_outcomes" is redundant and not necessary for an LTI link to be graded in Blackboard.
Resolution:
Check "Enable Evaluation" to enable the submit score button.
Problem #2
Symptom:
When examining an LTI payload created by Blackboard with outcomes or scoring enabled. The POST LTI payload has an "lis_outcome_service_url" but no "lis_result_sourcedid".
Resolution:
The user launching the LTI activity does not have a Student role in the class.