Sorry, no.
The statements “in the seen will be merely the seen” etc. are as Eddy says the way to train, i.e. the practice, i.e. the path, which is most definitely not Nibbana.
The text makes this clear by using yato … tato … constructions, i.e. “when this … then that”. The end of suffering arises from the practice. Perhaps this should be more explicit in the translation, but it is slightly clumsy English:
When you’re not ‘by that’, then you won’t be ‘in that’. When you’re not ‘in that’, then you won’t be in this world or the world beyond or between the two. Just this is the end of suffering.
The final sentence refers solely to the preceding clause, i.e. not being born in any world. My translation is fine, if anything the contracted form helps avoid this mistake.
Unrelated, something about Suddhaso’s construction here makes me uneasy. It shifts the emphasis to “there is” statements, which are not in the text, as there is no verb “to be”. This isn’t unusual for Pali, but, when “there is” is emphasized, it is present (atthi, bhikkhave …).
“You” is singular nominative, i.e. it is the subject of the sentence. Translating “you are not ‘in that’”, as most translators have done, keeps the emphasis on the (present) subject rather than on the (absent) verb.
I think the demonstrative pronouns here are deliberately ambiguous, as in such places they can convey a wide range of nuances. “By that” can mean “because of that”, (i.e. you are not created by that), it can mean “along with that”, “from that”, or “by means of that”, or something like Suddhaso’s “in terms of that”. Sometimes it is a good idea to narrow down the meaning in a particular context, but here I think the breadth is deliberate. It is saying that, no matter how you construe the these sense experiences, you cannot find yourself in any relation to them.