BW program (Operation T - FM Z_ZSF_CHECK_UPDATE_TIME )gets currency and credit limit data from:
Table KNKK need to input Bill to and Credit control area (KKBER)
Note: Bill-to gets from BW on table ZSF_ACCOUNTS
Credit control area gets from function module Z_ZZF_CM_KNKK in PF1
Source code in PF1 to determine credit limit and currency

We can determine Credit control area from function module Z_ZZF_CM_KNKK in PF1, KUNNR = Bill-To

Then, it will select KNKK base on bill-to and Credit control area, which returning from FM is "SOLV". In this example, once we select KNKK with KKBER = SOLV, we can find only 1 record, which is from customer 4007432


It will be EUR for 4007432. The rest will get from table KNVV and I summary below on your file.
The result that will send to SF, it will keep on table ZSF_ACCOUNTS in WBP, which should be the same as SF report.