The two Israelites weren't the best spies ever. They'd never been in a city! Most likely, they're walking around the city wide-eyed and pointing, strangely enough ending up in the house of a prostitute... Innocently... Right...
Excellent spying. Really. I wonder how Jericho's rulers knew exactly which house to go to when they decided to get a hold of them...
Rahab's the only one who speaks about Yahweh.