They dont need Therium to survive.
Yeah. I said it. The androids don't need Therium. Just think about it. Without the skin active, they don't scar and bleed like us. Look at the camps footage from almost any one and look for any Therium. Despite obvious brutality (and even shooting at points) no Therium is to be seen.
What about the Therium pump that is obviously seen being an important vital peice of the androids? Perhaps it's some kind of processor. As we see in the "last chance-Conner" scene (note never is Therium given to the androids to reactivate them despite losing.. Pretty well all of it) there's four vital parts that seem to depend on the model. The pumps may be some kind of regulator or diagnostics analyser and it is best to not operate without said peice so automatic shutdown was programmed.
Hole in my theory? More I should add? Let me know please!