Turn off gravity for this work.
You can try doing this over more frames, say 40 or 50.
Try values closer to default initially. Your rest-scale for instance, 0.7 might be a bit aggressive, try 0.95 to begin with, then 0.9, etc etc, same goes for pressure. Try 5, then 10 until you start to see what you want.
More substeps; you're using 2, try 8.
I wouldn't scale the zSolver to a large value, that might look like it's helping but in actual fact may be hindering. Scale the solver so the character is about 2m tall. (zSolver will be roughly half as tall as the character)
Let me know how you get on.