Chief. The hour meter is not always right. It is often changed, when a set gets a new engine, (but not always). Its often changed after reset, (but not always). It often goes bad. Do not put too much store in the hour meter is what I am saying.
The OP's problem was not the Flywheel, it was sheared off flywheel bolts. That will NOT happen unless the engine stops suddenly. I think there is more to be seen in this story. I saw, in the 8-9 years I was a contractor, 1 set that happened to. ONE.
If you want to check the bolts, you can. Got some spare time? It requires taking the set completely apart. If I bought a 802 or 803 I would certainly take it apart, down to the bits and pieces. But I have done a few times. I don't think you need to worry about something like this.
Most big gen sets, have a "Belt" that goes around the end bell of the engine, and the end of the main gen. You simple remove 1-2 bolts, take the "Belt" off, and can reach, (if your hands are small enough) into the space between the two peices of equipment and feel the bolts. If your like me, I had to use an off-set wrench, to get in and check them. This was one of my biggest complaints about these small sets. It requires a complete disassembly to get at those bolts.