No, pull works too. Lemmy doesn't support it, but technically you can pull the topic and then step through the collection. PieFed does support doing that (although NodeBB isn't always consistent at providing a JSON response, likely due to a CloudFlare caching issue).
If you want to do a pull that Lemmy supports from NodeBB, you need to choose the first post in the topic, not the topic.
E.g: https://browser.pub/https://forum.wedistribute.org/post/12
That just a Note (with inReplyTo null) that Lemmy will recognise as the equivalent of a Page.