Indirect "be" question; word order

Caveat: There are a great number of similar questions I have found, but none has explained this specific thing. If the answer does exist and I have overlooked it, please let me know.

So, I was under the assumption that the general rule for indirect question formation was to:

1. convert the question to a statement,


2. convert the unknown part to the appropriate question word, and


3. pull that question word to the beginning.

Thus:

Unknown object:

What does wasabi taste like?

1. Wasabi tastes like [something]. (converted to statement)


2. wasabi tastes like [what?] (replaced unknown part with appropriate interrogative)


3. [what] wasabi tastes like (moved interrogative to beginning)

Tell me what wasabi tastes like.

Unknown subject:

Who likes koalas?

1. [someone] likes koalas. (converted to statement)


2. [who] likes koalas (replaced unknown part with appropriate interrogative)


3. [who] likes koalas (moved interrogative to beginning)

Tell me who likes koalas.

If the subject is what we want to know, as in the koala example, we still do the same thing - pull out the unknown, convert it to a question word, and move it to the front - except it is already in the front, so the last step is superfluous. The formula remains the same, however.

---

This works for pretty much any situation as long as the main verb is not be. That's where I get confused.

Unknown... subject?

What is his name?

1. His name is [Bob?].


2. His name is [what?]


3. [what] his name is

Tell me what his name is.

This, to me, is the correct indirect question. Thing is, because of the fact that be is all copulationary-wise an' all, we can often reverse the subject and complement:

What is his name?

1. [Bob?] is his name.


2. [what?] is his name


3. [what] is his name

Tell me what is his name.

Now I know in speech this is probably quite common, but it sounds incorrect to me, and I would never write it. I believe (admittedly perhaps erroneously) that it is wrong. At least I think it is wronger than the first example.

So, my question: Is this 3-part rule I have been using wrong for be sentences? If so, what can I use in its place, and how can I explain it logically to my students?

---

Incidentally, the original question that sparked this was:

I don't know + Who is going to be our new boss?

Using the method above, this becomes:

I don't know who is going to be our new boss.

Whereas I think the more correct version would be

I don't know who our new boss is going to be.

but cannot explain why the former is incorrect.

---

I've looked around, and there are a few questions who come tantalizingly close but do not fully explain what I need to know:

Answer

I'm having a lot of trouble seeing the problem here. The fact that you are using a verb of identity makes no difference, except to allow for another acceptable way of phrasing the sentences. (And by the way, you could construct similar reversals even in the case of transitive verbs, if you wanted to, by using the passive voice, thus: "Koalas are liked by whom?" I wouldn't recommend it, and it's a bit unusual, but it's perfectly grammatical.)

As for the specific example (the "who our boss is going to be" vs. "who is going to be our boss" problem), each version is perfectly fine, perfectly grammatical, and perfectly acceptable. They are equivalent, and each is correct.