As part of an Interrail trip I'm looking at potentially riding the Little Yellow train and I'm trying to understand if the Interrail pass can be used on the Little Yellow Train themselves or if I need to buy another ticket. The Interail.eu site indicated that Interrail tickets can be used on SNCF services. Photos of the trains like this one clearly shows the SNCF logo on the front of the train. This website also states that:
"The Little Yellow Train,is part of the French state rail network, run by the French train operator SNCF. Consequently, tickets come at standard French train rates" which would suggest that Interail passes can be used.
However, the SNCF page for the line states that:
"Caution, during the summer, discount cards are not accepted."
We would be travelling in July, is the Interrail pass considered a discount card? If the Interrail pass valid on the line alone or is a reservation needed?