Sanjit,
Most of the data in VBAP and VBAK and LIKP and LIPS is not master data; it is transactional data, although some of the data contained in these 4 ECC tables is in fact copied from ECC master data at the time that the document is created.
Although some bits of ECC transactional data do exist in tables in APO, by far the most significant portion of transactional data does not exist in APO tables, it only exists in APO LiveCache. In general, it is not reasonable to expect that you will get 1-1 mapping of ECC data to APO data using tables only.
Best Regards,
DB49