Standardize values and type of outcome

[xbcsmith]

Changes

Submitter Checklist

As the author of this PR, please check off the items in this checklist:

• [ ] Has the primer doc been updated if a design decision is involved
• [ ] Have the JSON schemas been updated if the specification changed
• [ ] Has spec version and event versions been updated according to the versioning policy
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[e-backmark-ericsson]

See also #215

[xibz]

This does get rid of cancel. Should that be a value that we still need, though?