I'm able to get lolMiner working with two Vega 56's on Ubuntu 18.04.4 with amdgpu-pro-18.30-633530.tar.xz (legacy and pal both installed) by symlinking libamdoclsc64.so to libamdocl64.so and making certain I had the 'video' group on the user running the miner.

However, I'm with wojcieh and am only able to get 31-33 sol/s out of each of my two stock MSI airboost vega 56s (I undervolt them, but even at normal voltage I get max of 33). Are you seeing that 56 - 63 sol/s performance only on Windows? Did you make vbios changes?

That's a pretty amazingly dramatic performance improvement.