Please accept our apologies for any inconvenience this has caused.
Since the issue is within the PBS channel, we suggest reaching out once again directly to their support team to report the issue and for further help. Channels on Roku are maintained by the developers themselves. In this case, there's likely an issue within that specific channel that needs to be addressed with an update from the publisher.
You can contact them here: https://help.pbs.org/support/tickets/new
We appreciate your understanding.
All the best,
Roku Forum Moderator