I worked as a removal technician for a very busy mortuary service last year. Have handled more than my fair share of deceased people so I feel I can help with these types of questions. It is very common to find warm decedents if they have been covered up (care facilities/nursing homes, AFH's...
Companies I know of around here (I'm new too) are AMR - Fife, Rural Metro - Fife, Falck - Pierce County, Tri Med- Kent, Olympic Ambulance - Bremerton, Lacy. There's also AMR and Falck up towards Seattle and Northwest ambulance farther north than that. Hope I gave you one you haven't heard of...