From Lemmy you can see the accounts, but usually not their content (see note below).
@[email protected]
@[email protected]
Interaction between Lemmy and Mastodon doesn't work well because the two services structure their content differently. Lemmy is community based and Mastodon is user based. Lemmy doesn't have a mechanism to follow an individual user, and Mastodon doesn't have an analog to communities (afaik).
(Note: In the case of these two accounts, some of their toots are visible because they have been pulled into the [email protected] community as part of an experiment to bridge Lemmy and Mastodon.)