Yep you can clearly see the gasket is out of place. That will cause a problem for sure. Also possible since it's partially blocking the turbo oil drain with it cockeyed that you are getting oil backing up into the turbo and going somewhere - either into the exhaust or intake side.

You can do it with 1/4" drive tools. Also helps to get a 10mm 1/4" drive socket that has a swivel. Like this -


And some good long extensions.

As stated use something to tack the gasket in place so it doesn't slip out during reassembly.

Dale