This is apparently hard to understand for religious fundamentalists: Science is not a religion. It is not a fixed doctrine, but a permanent gaining of knowledge.

Observations that seemingly contradict previous theories come out every couple of weeks, especially in astronomy. Usually, the solution is found quickly. Sometimes however, astronomic observations lead to a modification of a theory, the development of a new one or - the last time in 1905 - even to abandoning a well-established theory.

This is however not to be expected for this one. Galaxy shadows on the background radiation are extremely weak. They can not be observed directly, but only indirectly through many assumptions and tricks. So the fact that they aren't found with a certain method can have a lot of reasons and is not so exciting at first.