Is there anything technically lacking from Blender that was used in these Maya/Arnold renders, based on volume displacement? I believe it's a camera based projection for the distortion for the most part.
How to Animate Boiling Water in Blender (With Bubbling Effect) - CG Cookie
How can I create a water material in Cycles? - Blender Stack Exchange
JLE Studios / i-U Asset Studios - Blender 3D Microdisplacement