Release 2728.3 and 29.0
The Native Currency preference must be setup in the Setup → Security → Client Preferences, Pref ID: SHOW_TOTALS_NATIVE

When the SHOW_TOTALS_NATIVE is set to ” $Y$ “, RMA, and Credit Memo screens will show the Native Currency over the Foreign Currency.
AR → RMA’s → Enter Edit RMA’s

RMA Print:

AR → Credit Memo’s

