“He was then taken to a massage room, undressed and lay on a massage bed.”
Let’s set aside for a moment the juicy question of “Who is this?”, and instead look at the even juicier question of “Why does this sentence feel a little awkward?”
The answer is found in the fascinating issue of parallel structure.
For a technical explanation, you can look at this post on grammarly.com.
In plain terms, however: Each of the elements in a series (this, that, and the other) needs to be set up the same way.
If the first item in the series is that he “was taken,” then each subsequent item in the series needs to be a “was” type of phrase too:
“He was then taken to a massage room, [was] undressed, and [was] lain on a massage bed.”
You don’t have to include “was” all three times, because it’s understood.
But I think what the writer really meant was: “He was then taken to a massage room, where he undressed and lay on a massage bed.”
It might have been less awkward to say: “He then went to a massage room, undressed, and lay on a massage bed.” (The active voice is often better than the passive.)
What happened next is anybody’s guess. (Active or passive. Ahem.)