I had a similar experience with rotten egg smell. We were woke up with the gas detector screaming. I smelled something but not sure what it was. We opened the door and reset the gas detector but in a short time it once again screamed at us. At first I thought it was sewer gas but ruled that out by dumping the tanks and flushing them. I then though maybe it was the ammonia leaking from the frig. Ruled that out and finally went to the front of the motor home and found the house batteries boiling. I had just put new batteries in the MH about 6 months ago. Took the batteries out and went and had them tested, all were OK. Went back to the motor home and hooked the batteries up and ran a voltage test on the converter, was putting 17.5 volts into the batteries. So ended up having to replace the converter.
