I'd say that it is the other way round: the Dacia should have French origin:
The first-generation Logan was designed at Renault's Technocentre near Paris, being the result of four years of development of the X90 project, announced by Renault in 1999, after the purchase of Dacia in the same year.
(Wikipedia)
For the Sandero, it is also French, but in cooperation with Brazil and Romania:
With a slightly shorter wheelbase than the sedan from which it derives, the Sandero was developed at Renault's Technocentre near Paris, France, in conjunction with the regional engineering centers based in Brazil and Romania.
So at least for that one the Romanian origin could be justified by that (in addition to the brand/make).