Mazel Tov, Bravo, Dan!
What a magnificent detective job Dan has done in tracing Elli and Helga's route from Toulouse to Lisbon! Like everything else you have done on this blog, you have brought to resplendent life events long lost to the sands of time.
One immediate thought; Helga did indeed speak about a "sealed train" crossing Spain to Portugal and that they were not able to get off the train at all...probably meaning that as it passed through Barcelona and Madrid, they were unable to get off the train. But maybe they didn't board the train until they had already crossed the border, as your research clearly indicates...I had understood from Helga's telling of the story that they crossed the French-Spanish border on the train and then continued onward, but the way she told the story could have allowed for them boarding the train on the Spanish side of the border...
Of course, one might say (to take an unkind cut at our wonderful late mother) if she forgot the name of her own grandfather, she might have forgotten some of these details as well :) Sorry Helga---anyway, She was pretty clear in several tellings of the story that I can remember going back to my childhood that it was a sealed train, so I would try to fit that point into the reconstruction of the event...I am thinking that I will call Valery Bazarov and ask him what he knows of sealed trains full of Jewish refugees crossing Spain to Portugal during this period...
Dan, your finding the Scotty Reston piece and the earlier one about the situation of the refugees in Lisbon was also magnificent...what an incredible elucidation of Helga's account...