Incorrect transaction type issue

[wqking]

It's reported that the transaction type is wrong in the wallet view. I reviewed the recent code change and found potential problem is in file src/qt/transactionrecord.cpp, in function TransactionRecord::decomposeTransaction, the code,

        } else if (isminetype mine = wallet->IsMine(wtx.vout[1])) {
            // VIT stake reward
            sub.involvesWatchAddress = mine & ISMINE_WATCH_ONLY;
            sub.type = TransactionRecord::StakeMint;
            sub.address = CBitcoinAddress(address).ToString();
            sub.credit = nNet;
        } else {
            //Masternode reward
            CTxDestination destMN;
            int nIndexMN = wtx.vout.size() - 1;
            if (ExtractDestination(wtx.vout[nIndexMN].scriptPubKey, destMN) && IsMine(*wallet, destMN)) {
                isminetype mine = wallet->IsMine(wtx.vout[nIndexMN]);
                sub.involvesWatchAddress = mine & ISMINE_WATCH_ONLY;
		if (nIndexMN == 2) {
			sub.type = TransactionRecord::FNReward;
		} else {
			sub.type = TransactionRecord::MNReward;
		}
                sub.address = CBitcoinAddress(destMN).ToString();
                sub.credit = wtx.vout[nIndexMN].nValue;
            }
        }

That was changed according to PIVX upstream, except the conditon for FN and MN reward is for Vitae. I think that conflicts with FN and MN logic.
The code before the change is,

        CTxDestination destMN;
        int nIndexMN = wtx.vout.size() - 1;
        if (ExtractDestination(wtx.vout[nIndexMN].scriptPubKey, destMN)) {
            if (IsMine(*wallet, destMN)) {
                isminetype mine = wallet->IsMine(wtx.vout[nIndexMN]);
                sub.involvesWatchAddress = mine & ISMINE_WATCH_ONLY;
		if (nIndexMN == 2) {
			sub.type = TransactionRecord::FNReward;
		} else {
			sub.type = TransactionRecord::MNReward;
		}
                sub.address = CBitcoinAddress(destMN).ToString();
                sub.credit = wtx.vout[nIndexMN].nValue;
            }
        }

Any clue on what the vout index of master node is so we can fix the index check?