2020 Kubota RTV-XG850 Gas in the oil / Backfire, loss of power?

[catalyst]

We own a 2020 Kubota RTV-XG-850, with only 400 hours on it and it has been at the dealer 3+ months. We were just informed our engine failed and requires a complete rebuild at only 400 hours! There is a loss of compression in cylinder #1, which is causing backfiring and a loss of power. There is also excess gas in the engine oil. 
We are just outside of the manufacture's warranty period, and they are serving us a nearly $5000 repair bill, with only a 90 day warranty.

A member at a different forum had the same issue at 22 hours and fortunately, his RTV is under warranty. He was informed that "short tripping" (as Kubota describes it) causes gasoline to enter into the engine oil, which causes a dilution of engine oil and eventually leads to catastrophic engine failure. This killed our engine in under 400 hours!

Is anyone else with a 2018-2022 XG-850 running into similar issues?

 

 

[motojoe]

It appears that there is something wrong with either the carburetor or the fuel injection.  If it is carburetor engine then the needle and seat is not sealing or your fuel pump is staying on.  If it is fuel injected then your fuel pump is staying on when the engine is off.  Either way make sure that your fuel pressure is fixed before you run the new engine or it will fail again.