If you have a SuperTigre G-75 that's been purchased in the past few years, the connecting rod for the S-75/G-75 is the correct one, and the one from your engine should be identical. It is possible, however, that if the rod you recently received is longer than the one you took out of the engine, you got a package with the wrong rod in it. We'd need to see it to be sure.

If you do have the correct rod, then we'd not know what would cause your engine to jam at Top Dead Center, unless there's some debris or the ring is catching a port.