I have a Totota Camry le 2001 2.2 v4 with 177,000 miles which is leaking oil! My question is whats the real cause?????

Clearly, these mechanics don't have a clue any more than you do. You have one guy saying it's on the top of the engine, and the other guy says it's on the bottom. The only way you will figure it out is to degrease the engine, wash it down, and try and locate the oil leak yourself. Then take it in and tell them to fix it. These clowns will replace every oil related gasket on the entire car. The people here on this site can't diagnose an oil leak without looking at every component ourselves. We would only be guessing like those lazy mechanics. I would not bring my car back to either of those two guys. Go to your local auto parts store and ask for some UV oil dye. You will also need a UV flash light. Buy some engine degreaser also. When engine cools, spray degreaser on the problem area. Spray down the engine with clean water. Let engine dry. Put in the dye and run the car. Shine the UV light around the engine and you should see a very visible area with the dye. That should be where the leak is. At least now you can pin point the leak and tell the mechanic where it's coming from. Here is a short video on how it works. https://www.youtube.com/watch?v=OgsqmMjC5So