The key to that is the Earth Juice is organic and there is not a need to pH adjust because it is organically chelated with microbes. Once an organic setup is running and balanced, adding the earth juice, even though it has a different pH, will not hurt the system because the microbe herd will control the pH. Also, when running organic soil, one should have a sufficient amount of dolomite lime added to it to buffer the soil to acceptable levels.
I have used the Earth Juice with Jungle Juice and had excellent results but there is a trick to mixing organic nutrients and synthetic nutrients. Normally, you shouldn't mix liquid organic and synthetic nutes, but AN says that these 2 can be mixed together but you have to use Hygrozyme in equal parts with the earth juice so that it can be beneficial to the plants.
Now there is another issue that can cause you grief with pH and that is your source water. If the pH is way off in one direction, that can cause you problems. Also, if the source water has an abundance of dissolved chemicals such as high amounts of lime or heavy metals, these can have a profound affect on your solutions. I always recommend that people have their water tested for TDS prior to beginning a grow.