Our infrastructure requires us to build project into \bin\output , rather than \bin.
It appears that Sitefinity looks for assemblies in bin folder by default.
Sitefinity support has suggested adding assemblyBinding configuration setting:
Telerik assemblies still don't get picked up, but non-telerik assemblies are now being picked up, which is better!
Did anybody manage to get Sitefinity to run from a custom build directory?