Unfortunately, it's incredibly difficult to make the bad trader report system any better than it currently is. Unfortunately, people with lots of references and huge trade history do steal from new members.
Here's an example:
Basically, when I was new to the site, I was trading with someone who had way more references than you. They had maybe 50 or more references. They picked this point in time to keep everything that was sent to them first and not send out anything where they were sending second. This was the only trade when I had cards stolen from me; the lost cards included a charizard and a boxtopper. As you can see from the link I provided, I had used tracking to prove that my part of the trade had been received so it made filing a bad trader report a lot easier for me. Besides stealing cards from me, they also stole cards from 8 other people, which you can see here:
Here are some tips for how to protect yourself:
1) Keep very good communication with people you are trading with. If you have to mail cards late, let them know why and when you will be shipping. Don't mark off your part as sent until after you have sent the cards.
2) For international trades, make sure that the person you are trading with understands that it may take a month or more to receive cards from you. If they aren't willing to wait more than a month for each end of shipping to take place, don't trade with them.
3) Fully tracked international trades are often prohibitively. I usually only have a US customs number to show that my part of the trade has left the US (I am usually able to get a customs number whether I use a package or a letter).
4) If you see that someone hasn't received cards from you after a lot of time has passed, check up on them to see if they have received the cards. If you have something similar to a US customs number, ask if they would like you to check on the status of whatever tracking you have. Personally, every time I have checked up on someone, the response is typically along the lines of "Don't bother checking the customs number yet, I wouldn't be surprised if it took a few more weeks for the cards to arrive and I'm not worried."
5) Do everything you can to make sure the person you are trading with is happy. If something is lost in the mail, send them a new shipment or compensate them monetarily (personally I've never had to compensate someone monetarily, but I would if I had to).
6) Before you decide to accept a trade, consider how likely it is that the person you are trading with could lie and claim they never received cards from you. If someone seems untrustworthy, don't trade with them unless you can afford tracking or you can afford to compensate them monetarily if they lie about receipt of your cards. You should also consider the shipping costs of the trade before accepting. If an international trade's value is not much more than the shipping costs, don't accept that trade.
7) If you have a bad experience with someone, don't trade with them again.
8.) When you have active trades, you should be checking the website often (more than every 3 days) to make sure there are no problems. If someone messages you about a problem and you don't respond within a day or two, they will be concerned and more likely to file a bad trader report. The ability to respond to an admin message within 3 days shouldn't be a problem because you should already be on to check that often anyways while trading.
9) Keep in mind that children do use this site and may not understand how shipping, tracking, or international trades work. Be extra careful if you think you are trading with a very young member of the site.
10) If a trade times out for any reason, contact the person you are trading with immediately.
Keep in mind that bad trader reports are reviewed by the admins. This prevents people from filing false reports. In your case, the person you were trading with most likely didn't wait long enough before filing a bad trader report because the international shipment may have taken a month or two to reach them. It also looks like the person you were trading with has had cards stolen from them before even though they have been using this site for a very short amount of time, which is something you should be extra sensitive to.
If you have any questions for me about trading tips or the report system, let me know! =)