Fuel in Oil

[Atlas]

I have a CM2250 with 840,000 miles. About 7 days ago noticed that engine at idle sounded noisier. Later in week plug in Insite and came up with code 553, rail fuel pressure higher than normal, codes 271, 2311, and 272 telling me that fuel pump actuator circuit was intermittently open or shorted. Immediately check 2 wire connector from fuel pump actuator. It was loose. Fixed that, cleared codes. Engine ran better and codes did not reappear. Check oil level and noticed it had risen about 1/8 of inch on dipstick. Coolant level was unchanged. Changed oil and filters. Seemed like a greenish tint to oil. Ran fuel system leakage test 3 times, no psi drop. Fuel pressure stayed steady at about 29000 psi. My question, is it possible for fuel to get in oil and where? Should i drive truck and monitor oil level everyday ?
Little background. I did a inframe at 830,000 miles excessive oil consumption. In addition to basic overhaul, replaced all 6 injectors and injector tube rail connectors. Replace fuel pump with updated version about 6 months prior. Thanks for any input.