From what I hear there was a line in question in the last version which allowed trusted nodes to send sc to the CPF (PUBLIC WALLET FUND FOR SC) ("if( x < y)" where it should have been a "if(x != y)"). This only allowed trusted nodes to send money to the CPF, but the CPF account is public and if any foul play was detected everyone would know instantly.
Actually, I think the code that's meant to restrict them to only send to the CPF has a security hole the size of a barn door too. Also part of the problem is that even if everyone did find out promptly it'd be damn difficult to actually do anything about it aside from writing it off as a fait accompli. It's not like we can run SolidCoin without RealSolid and his trusted friends (if they even exist).
Since then the trusted nodes have been patched with the latest version, and they are preparing it for public release soon. That is one of the advantages of having everything open source (which I always advocated for), problems like this become detected and get solved.
Which of course is why RealSolid is so opposed to it. This code was included intentionally, he just thought he'd fixed it before the open source release.
To "take over the network" you need both a trusted node with more money than any of the other trusted nodes on the network and 51% of the network hash power.
I don't think it's possible for that to be true because of symmetry. In order for it to be impossible for someone to take over the network unless they have a trusted node with more money
and 51% of the network hash power, it'd have to be possible for another trusted node with more money but less than 51% of hash power or less money but more than 50% of hash power to override it. But that contradicts your original statement that you can't take over the network without both!