A new paper is out online:
Gallina, P. A., Canale, J. I., & Carballido, J. L., 2021. The earliest known titanosaur sauropod dinosaur. Ameghiniana 58(1), 35-51. https://doi.org/10.5710/AMGH.20.08.2020.3376
Ninjatitan is recovered as a basal titanosaur in the cladistic analysis by Gallina et al., making it the oldest primitive titanosaur to be described and at last synchronizes the basal titanosaur fossil record with the timing of the divergence between titanosaurs and other somphospondylans in the earliest Cretaceous.