For Treasury postings like tcode TPM1,TPM44 and so on, the postings are performed only in local currency 1, and there is no amount in local currency 2 (group currency) or local currency 3, or in TBB1 the amount is unexpected.
Treasury does not directly support a second or third local currency. The Transaction Manager works only with the first local currency and transaction currency. Therefore the second or third local currency is not filled from Treasury Management.
Here is one easy example why a valuation posting (by TPM1) cannot provide all currency amounts in one posting: Suppose we have a position with position/ document currency HKD, 1st local currency THB, second local currency USD. Before the valuation, the book value (in respective currencies) is
1000 HKD 800 THB 125 USD
At the valuation key date, the FX rates change such that the market value at the key date is
1000 HKD 830 THB 120 USD.
Thus, a write-up in 1st local currency THB (800->830) and a write-down in second local currency USD (125->120) is required. But one FI posting can be either a write-up or a write-down. Moreover, since write-up and write-down usually effect different P/L accounts, different documents are needed to post to different accounts. That's why a valuation for multiple currencies can not be done in one accounting document.
Furthermore, a usage of different currencies usually implies different accounting principles (like local-GAAP, IFRS and US-GAAP). Different Available for Sale vs. held to Maturity) and measurement/valuation (market-to-market valuation vs. amortized cost).
It is necessary to use separate valuation areas in Treasury in case multiple currencies and/or multiple accounting principles are needed. If an additional valuation area is used to determine the amount in second or third local curreny than you do not have the problem with the different translation (posting date) because we send the amount to FI. This way, the FI postings will carry the correct LC1 and LC2 amounts.. Please refer to note 1557972 for detailed information.