Annaz,
I'll share a few things that may be of help in gaining a new perspective about this particular assignment.

Often when we, as the teachers, have a different goal than the goal which the text has, we will find ourselves at cross-purposes with the text. I know you've shared in the past some similar frustrations with a previous assignment in WWTB like this, and I honestly think much of the frustration comes from being at cross-purposes.

I know this was true at our house, when we were completing this type of assignment in WWTB the first time it came up too.
To explain more fully, I'll share that my first inclination when I came to this type of assignment was to assume my kiddos should be able to find the nouns/verbs/adjectives/adverbs in the passage mainly on their own.

As the assignment progressed, and my children struggled mightily in this task I jumped in to help them thinking this can't possibly be that hard! I was amazed at the sheer number of each of these parts of speech within the passage and found myself trying to find them all alongside my kiddos.
Later, after going back and re-reading the directions, I realized that the intent of the assignment was not for kiddos to find "all" of these parts of speech and nor was the intent for this to be a grammar lesson.

These were the two intents that I had focused on within the lesson, leaving me at cross-purposes (and frustrated) with the text. Instead, the directions mentioned that the kiddos should not be expected to find all of the nouns/verbs/adjectives/adverbs. Consequently, the key in the back is just to help as a guide and is likely not exhaustive either. This is because the intent of the lesson is to show kiddos how much description good writers use within their writing.
In order to show how many adjectives are included, it is often necessary to first find the nouns. In order to show how many adverbs a good writer uses, it is often necessary to first find the verbs. So, this is what the lesson does. The lesson also desires to show kiddos that excellent writers use specific nouns and verbs rather than the general run-of-the-mill variety. This is also accomplished in the lesson.
You can see the difference in goals as we, as the teachers, focus on this as a grammar lesson, and the text focuses on using the parts of speech merely as a demonstration of how to use description and specific words within a piece of writing.

With this in mind, the next time the lesson came around I was prepared! I found it helpful to write myself a note to remind me to limit the number of nouns/verbs/adjectives/adverbs that I required my child to find. I also made sure I was there to help mightily with the assignment on those days especially.

Next, I focused on looking over the patterns that we found with the circled words in the passage, and I focused on the sheer volume of descriptive words in the passage. Last, we took note of the specific nouns and verbs we'd circled and talked about how interesting these word choices were. Then, we closed the assignment out. I made sure not to drag the lesson out, and I focused on the goals for writing, rather than my goals for grammar.

Hopefully, this will help you too as you continue on with WWTB.
My kiddos truly enjoyed using WWTB, and I saw such good growth in their writing skills.

It is also important to note that this particular type of lesson only comes up 7 times out of the 70 days WWTB is scheduled. It is only meant to open each unit to set the bar very high for the student's writing, which is truly does!

I think you'll be pleasantly surprised too what your daughter will gain through her time spent with WWTB if you don't allow yourself to get bogged down at cross-purposes with the text.
Blessings,
Carrie