Wow, tough situation for all of you. If your house is the only place he won't sleep, then there's something different about your house that is unsettling him.
Some babies need far more burping than they actually get. If he sleeps on you in a somewhat elevated position, but becomes uncomfortable when lying flat, then he could be suffering from pressure in his tummy. Some babies hate being transferred from a warm shoulder to a cool bed, but might do okay if the bed is pre-warmed with a hot-water bottle, or held until they reach the limp-arm stage.
Find out from his mom if he's used to any particular thing in his own bed: partial light or complete darkness, a sound machine or soft music, a specific bedtime routing that might include something like back patting. Even the two hours leading to bed can make a difference – some kids need lots of action to burn off excess energy, but for some that would only overstimulate them. Exposure to TV can really mess with a baby's brain wave patterns and make them anything but sleepy. Also, shorter or missing naps during the day might leave a child less able to sleep at night. You might even try a blanket or piece of clothing that smells like his mommy.
Also check the chemical situation that he's exposed to at your house. There are many new chemicals in modern cleaning supplies, fabric softeners and scented detergents, and air "fresheners" that are actually quite toxic and irritating to the nervous system, and a senstive child might simply be unable to sleep. I've known a few littles who became much more relaxed and better sleepers when these irritants were removed.
Finally, many, many babies become stimulated when they're about to reach a developmental breakthrough, standing, walking, or learning words. Their little brains go into overdrive. Eight or nine months is a common time for one of these disruptive cycles to hit. Is it possible that his mommy simply doesn't hear him when he cries at night?
I sure hope you figure out something that works.