I looked through the mod files and changed some things in the config.lua file and i think they some things should be changed:
Line 14,15:
injector_oil_min_yield = 250
injector_oil_max_yield = 500
to
injector_oil_min_yield = 2500
injector_oil_max_yield = 5000
and Lines 20,21:
dynamite_oil_min_yield = 125 -- minimum oil revealed by a dynamite
dynamite_oil_max_yield = 250 -- maximum oil revealed by a dynamite
to
dynamite_oil_min_yield = 1250 -- minimum oil revealed by a dynamite
dynamite_oil_max_yield = 2500 -- maximum oil revealed by a dynamite
This should bring the oil yield to proper levels, I forget which update it was that change fluids, but everything was multiplied by 10 at one point so simply adding a 0 to those lines should fix the issue.
Edit: 0.15 Was the version it was change in:
https://imgur.com/a/XT5xxkH