The 2019 AVZ copyright graphic in the article has an on Lake...

The 2019 AVZ copyright graphic in the article has an on Lake Tanganjika south south east route from Moba to Mpulunga marked in blue dots. I don't recall seeing that before. It could be a contingency or alternative that is under consideration if road development around Pweto is too slow (to refurb or construct) or too expensive. Existing roads to Moba from Manono may be better than Manono via Pweto currently (and perhaps in near future) and from Mpulunga (lake port) onto road again to a rail siding at Nseluka could be under consideration.

I guess a thing about a Lake transport section is it probably can't be blocked (by a broken down vehicle) on the Lake itself or flooded out like a road section might be.

From memory the Manono to Moba road route itself involves a need for a barge at one point though as the river there hadn't been bridged.