Put simply, most likely no. It would probably 'fruit' something/s, whether they be the things your after, i doubt it.
The current methods used to fruit the mushrooms humans seem to have an affinity for are relatively easy, they may not seem like it but they are. The reason your idea won't work and something like the PF tek will is beacuse the PF tek decreases (considerably) the chances that any other fungus or bacteria will grow on your chosen media.
IF you stick a cow pat in a box, saturate it and keep it at room temperature you will end up growing the most prevelant and successful bacterias or fungi that are present in your house, flying about on the breeze.
Read the PF tek a few times (until you can repeat it back to someone else) find spores or culture of the mushroom you want to grow, follow said tek to a tee and i guarantee you will have a most desirable out come.
p.s. ALWAYS conserve water.
PF tek
erectus.