Complex sentence: If either of them had helped the Tecks then surely this would be public knowledge because it would reflect to their credit, so the fact that there is no such public knowledge is a clear indication that some other party rescued the Tecks financially.
Split into simpler sentences: If either of them had helped the Tecks then surely this would be public knowledge because it would reflect to their credit? The fact that there is no such public knowledge is a clear indication that some other party rescued the Tecks financially.