1997 BMW 740 Oil Pressure Light

I have a 1997 BMW 740iL 4DR sedan. It currently has 181,000 miles on it. Up to this point it had been running fine and has been regularly maintained. In November of 2008 I was driving on the highway heading home at about 11pm. The car was running great as it always has. I decided to quickly put the pedal to the floor to as I believe (clean out any loose carbon deposits). Immediately, I heard a loud noise. However, nothing on the gauges indicated a problem for
about 2-3 minutes later. It seems when I did that the fan and clutch pully came apart damaging the radiator, hoses, and hood. I immediately pulled the car into a roadside restaurant (Burger King) as it began overheating. After inspecting the vehicle I called a tow truck to have it brought to my mechanic. I turns out that due to my collision coverage everthing but the cause(possibly worn or loose clutch fan and pully) will be covered. Prior to putting the allowed parts on the car I requested that the shop run the engine to check for any other damage. They state that they would do that. A month or two later and many conversations with the shop and the insurance company I receive a call from the shop informing me that the parts are replaced but that the car oil light will not go out and after questioning them, that it has little or no oil pressure. Well I am shocked because the car never had oil pressure problems and the oil light never came on before. When I inquired as to what might be the reason for this and could it be caused by the collision damage, I was told that the oil pan gasket got sucked into oil clogging the pump and screen and that this happens with cars with such high mileage. I told them I didn't understand since I have owned many cars with high mileage and never experienced that and have never heard of it. The shop also told me that someone must have put some gasket material on the oil pan that got sucked into the oil pan. I bought the car 8 years ago and no one has ever opened the engine. I had the insurance appraiser go out to look at it and they stated it looks like the possibly the gasket got sucked into oil pan and of course is not covered(which I expected).
---My real concern is that I am wondering if something got into the oil whether vandalism or otherwise to cause this. ---In my limited understanding, there argument suggests a process that takes years and that this happened in a two month period while the car was in their shop parked and not being driven. Pardon me, but non of this makes sense to me but I need an expert opinion! My options are lay out approximately another $2000 from my limited funds or go to court with the insurance company to establish that something else
happened while in the shop. Thanks in advance for your input.