Good points op. I think it is the us agent who has subcontracted to the other markets, I’m not sure though and yes, it would possibly be under their markets law.
I'm pretty sure one of the reports described it as his "UK agent", UTA. I agree, if this is just the UK office of UTA USA (rather than a separate English governed legal entity), then the licensing contracts to the foreign language publications may be governed by a US state law.
im not quite aligned on scobie being responsible if the agent made an error. The agent commits contractually to do certain acts. It is not for the author to then audit them to ensure they did, they have a right to a reasonable expectation the agent can carry out the duties they agreed to. If the agent failed, they are responsible. Not the author for not going into their business and checking.
There's a difference between OS and UTA's legal relationship and the relationship between Xander and UTA/OS. The whole point of agency is that third parties can reasonably assume that the agent is working under the instructions of the principal. In this instance, Xander have the reasonable expectation that anything they were instructed to do by UTA is the instruction of OS. Further, Xander's contractual relationship is going to be with OS, not UTA. If Xander were to sue OS relying on the contract, then I think they would be successful, even if their instructions from OS came via a third party. It would then be up to OS to in turn sue UTA for breach of their contractual/legal relationship, and he'd need to show that UTA went rogue and did something either negligent or completely contrary to OS's instructions.