2002 Cadillac Escalade PO 307 MISFIRE PROBLEMS

Ok I am a technician on Electrical Motors and know some things about vehicles. I have a OBD and did a test and came up po307 misfire on #7. I took it to a Chevy dealer. They told me it was a fuel pump low pressure. I didnt believe them but put the fuel pump on anyhow. I still have a po307. I decided to change all plug wires and Platinum Plugs with GM recommended plugs. I still have PO307. Today I changed the coil 7 with 5 and problem satyed with 7. I also noticed number 7 plug is very wet and fouled looking every time I change it. I went as far as tracing out wires to the injector and they are fine. I also ohmed the injector came back with 16-17 ohms just like the injector next to it. I am going nuts. I do not want to drive the truck running rough like this and am getting sick of paying mechanics to throw parts at it. Mileage is also down to 10 mpg. Do you think the injector is stuck open on #7. Is there any way to check this injector? I also pulled the plug wirte and put a different plug on it and layed on exhaust manifold. It does have spark.

i repaired it. Was and in injector cleaned with gumout runs great now!