[joe_the_user]

The linked Wikipedia article considers the substance that organs rest on, such as the pericardium, to be part of the fascia system. Though the muscle fascia and organ fascia distinction is worth keeping in mind, the article implies that tubes have been found in both.

Also, I think whether these tubes are part of lymphic system is speculation at this point. The main thing is that they havne't considered in anatomy because they're destroyed by embalming.