correct tx tree determination logic

server/asset/dcr/dcr.go

@@ -932,14 +932,30 @@ func (dcr *Backend) getTxOutInfo(ctx context.Context, txHash *chainhash.Hash, vo
 	if err != nil {
 		return nil, nil, nil, fmt.Errorf("failed to decode MsgTx from hex for transaction %s: %w", txHash, err)
 	}
-	txTree := stake.DetermineTxType(msgTx, msgTx.Version == wire.TxVersionTreasury)
-	txOut, pkScript, err := dcr.getUnspentTxOut(ctx, txHash, vout, int8(txTree))
+	tree := determineTxTree(msgTx)
+	txOut, pkScript, err := dcr.getUnspentTxOut(ctx, txHash, vout, tree)
 	if err != nil {
 		return nil, nil, nil, err
 	}
 	return txOut, verboseTx, pkScript, nil
 }
 
+func determineTxTree(msgTx *wire.MsgTx) int8 {
+	// Try with treasury disabled first.
+	txType := stake.DetermineTxType(msgTx, false)
+	if txType != stake.TxTypeRegular {
+		return wire.TxTreeStake
+	}
+
+	// Try with treasury enabled.
+	txType = stake.DetermineTxType(msgTx, true)
+	if txType != stake.TxTypeRegular {
+		return wire.TxTreeStake
+	}
+
+	return wire.TxTreeRegular
+}
+
 // Get the block information, checking the cache first. Same as
 // getDcrBlock, but takes a string argument.
 func (dcr *Backend) getBlockInfo(ctx context.Context, blockid string) (*dcrBlock, error) {