Can a low immune system make lyphm node swell and will taking a multi vitamin help the swelling down? can they still go down if it not low immunity

Possible: However it is usually the body's immune response to an invader that makes the lymph node enlarged. You should be more concerned about a thyroid nodule and ask your doctor to check your neck for you. Vitamins would not do anything for you.

Fighting infection: Lymph nodes swell up to fight off infections.Swollen lymph notes usually mean that the body is doing its job to try and get rid of infections. Vitamins will not help the lymph nodes to go down. Once the infection is resolved lymph nodes usually go down. If lymph nodes do not go down after months, then you should see a doctor for further testing. Persistent lymph nodes can be a serious problem.