How to handle Supplementary Instruction of Subject-Deficient Students with language difficulties I work as a supplemental instructor for students that come out of high school with subject deficiencies. They are admitted as conditional students, and they are required to meet certain benchmarks in order to proceed. These subject deficient students are required to take supplemental courses alongside their first lecture in whatever subject they might be deficient in. The instructors for these supplemental courses, or enhanced labs, are all undergraduate students. We work alongside the professor of the lecture to develop lesson plans that coincide with one another. For example, in a Statistics lecture, the professor will only teach statistics, but in the lab, I work to teach algebra components they missed (or forgot in the case of non-traditional students) alongside reviewing the statistics covered before tests. 

Typically, the number one problem is that these conditionally admitted students are on completely different levels from one another. This has its own solution that has always worked well. 

That being said, another problem has arisen. I have a student in my lab that speaks very little English. Due to this, he has been struggling severely but hasn't dropped the course due to an incredible perseverance. The issue at hand is that I have absolutely no idea how to support him as an instructor and the professor I'm working with is also at a loss. When consulting with the Academic Support team, they're also at a loss, because we don't have a lot of support for languages from his region.

How should I go about handling this student? At this rate, he will assuredly fail, and I don't want to just leave him to drown. Collegiate statistics can be hard enough for students as it is.
assuming that this student met the English proficiency requirements of your school it is still common for esl students to fail courses due to language issues. this is due to the fact that they have to acquire the language of the course in addition to everyday English.

if you are willing you can try to accommodate this student through providing additional teaching and or additional time for assignments and assessments. 

from personal experience for a hard working esl student the second time through id always a charm. as their language skills improve the chances of repeating are drastically reduced.