Welcome to 2CarPros.
Did you replace the bypass hose (small one off water pump)? Next, if it isn't that hose and the leak is behind or under the AC compressor, have you checked for an intake manifold or head gasket leak?
I attached two pictures and circled on thing in both. Tell me if the hose was replaced in picture 1 and if the leak appears to be behind where I circled in picture 2. Also, picture 3 shows the engine coolant temperature sensor's location (right next to the thermostat housing). Confirm it isn't leaking.
Here are a few links you may find helpful. The first link discusses a bad water pump and where it can leak from. The others are to help locate the leak. Since you did pressure test it and the leak seems to be near the AC compressor, you may have to remove the compressor to get a good look at where it is coming from.
Let me know what you find.
Images (Click to enlarge)
Wednesday, May 29th, 2019 AT 7:05 PM