Out of curiosity, I checked into the two staff members we've heard about (aside from the artist).
Shohei Sato, who is listed as the director, actually has some prior connection to Langrisser/Masaya. Mobygames lists him as being given a special thanks/technology credit in Langrisser V and was also a producer and group manager for the 2009 revival of Cho Aniki. Prior to working at Extreme, he was a GM at Masaya's parent company (which may explain his credit in L5). Weirdly enough, Extreme's own website says Sato is actually the President/CEO of Extreme, not Soshi Saito.
Soshi Satio doesn't seem to pull anything up that isn't news about Langrisser 3DS working off the same translated source, so maybe there's a mistranslation/miscommunication somewhere in there.
Extreme's history also makes it seem like one of the first major things they did after they were established was to work out a deal with NCS to work with/manage Masaya properties in NCS's place, so I wonder if maybe Extreme is actually a bunch of Masaya alums splitting off from the parent company to function on their own (not that it means much for Langrisser, since we know where the main people behind that went).