JE for secondary ledger

We are in Oracle EBS R12.2.x

Could you clarify for the below scenarios if we enable "Use Primary Amounts flag" to YES, is enough to meet the requirement of creating Journal Entry (JE) into the secondary ledger or Is it always necessary to create Tax book association to the secondary ledger and transfer the JE to the SL.

Our Scenario:

1 Primary Ledger (PL)

1 Secondary Ledger (SL)

All C's are same except the accounting convention.

Journal Conversion mode - Subledger Accounting

1 Asset Book and 1 Tax Book

The Asset Book linked to the Primary Ledger and NO association of Tax book to Secondary ledger