Do players get PDGA ratings from league rounds?
Yes. Current PDGA members will earn ratings and even non-members will earn them even though they won't be able to see their official ratings until they join or renew. Players will see unofficial round ratings each week when the league director posts the scores online just like regular tournaments.
If some weeks don't display unofficial ratings, it's likely not enough players entered that week with established ratings (propagators) over 699. At least 3 propagators are required to produce unofficial round ratings. The good news is that once the league report is submitted to the PDGA, players will still receive official round ratings for any of the weeks they couldn't see unofficial ratings.