Of greater concern is the engine oil thermostat, which is still not opening. You declined that operation in the past, which is understandable due to the large cost of repair at that time, but it still isn't opening, and thus your engine is still susceptible to overheating and seizing, which could destroy the engine altogether.
The attached quote for that repair includes engine oil cooler hoses, some or all of which may or may not also need to be replaced; Paul would be able to ascertain the condition of those hoses after removing the failed oil thermostat.
Now, I am a little confused about the thermostat. I was under impression that we replaced it on 6/5/2012, invoice #4110. I did notice that (supposedly) replacing it did not change the condition of oil warning light coming on all that much, though.
Please let me know what you think.