You mentioned API v33 and RunLocalTests. I can not see any mention of RunLocalTests in Metadata API doc v33, so have to assume you meant v34, not v33.
If my assumption about the version of Metadata API is correct then you are probably having the issue described here: Metadata Deploy - test code coverage report is broken in Metadata API v34.0 (Summer 15). Test implementation in Metadata API v34 does not report coverage for classes not included in the package.
Workarounds:
- include (in the package) all classes for which you want to get coverage
- or use Tooling API
- or downgrade to Metadata API prior to v34. For instance v32. v33 will probably also work but I did not test it.