4 different opinions from surveyors-who do I follow?

I'm so confused! 4 different opinions from surveyors on causes & management of our rising damp.We have a 20 yr guarantee with Peter Cox-who are refusing to do the works as damp is coming from the floor-they say.They gave an incurate report stating low level of moisture-where 3 other surveyors detected high levels of moisture rising 1 metre.What shall I do? I don't know who to follow. Thanks, Shuyee