I can reproduce the issue, thanks for the file.
There is an error in the SketchUp SDK itself, it returns “SU_ERROR_SERIALIZATION if the serialization operation itself fails”
There is no more information, so I don’t know what the issue is exactly. I’ll ask Trimble what this can mean.
Keep in mind that the SKP file format tends to produce very large files compared to other formats like FBX.
So a 274MB .fbx file is bound to produce a huge .skp file, probably in the realm of several GB. Maybe that’s the issue, the SDK might not be able to create such large files.