[PHI 1000] What's it like and explanation

In "What is it like to be a bat?" Nagel says the following:

if facts of experience—facts about what it is like for the experiencing organism—are accessible only from one point of view, then it is a mystery how the true character of experiences could be revealed in the physical operation of that organism.

Here, Nagel seems to be arguing as follows:

1. Facts about what it is like for the experiencing organism are accessible only to that organism.
2. Therefore, the true nature of these subjective facts cannot be explained by the physical operation of that organism.

Put differently, using Nagel's example:

1. Only a bat can experience what it is like to be a bat.
2. Therefore, what it is like to be a bat cannot be fully explained by reference to the physical operation of a bat.

What do you make of this argument? Does it follow that no complete physical explanation can be given for facts about X from the claim that such facts are accessible only to X itself? For example:

1. Only a dog can experience what it is like to bark.
2. Therefore, barking cannot be fully explained in physical terms.

What are the implications of this argument for the notion of explanation? For example, biologists claim to have explained why bees engage in "dancing" behavior. The explanation involves the claim that this behavior is a form of communication. But, if Nagel is right, have biologists really explained this behavior? After all, there are facts about this behavior that are accessible only to bees, namely, facts about what it is like to waggle dance.