I’m no graphic designer, but I probably think they used Photoshop and/or Cinema 3D, since I think I’ve seen those type of art in Juan’s Graphics or Preville Graphics.
I can agree with you regarding the programs you mentioned, I’m a graphic designer who uses Photoshop and Cinema 4D (its 4 not 3 ) and I would be able to produce similar.
I would recommend using blender for the render of the characters, but just either make a background or find an image that ISN’T someone elses or copyrighted!