Update: LS-PrePost included in Ansys Student 2023 R1 is probably faulty, and creates incomplete bat-file. It worked fine when I downloaded new version of LS-PrePost.
A question remains: does Ansys Student 2023 R1 have a license for LS-Dyna included or is product called Ansys LS-DYNA Student needed for that?
They both have LS-Dyna executables included. I cannot check it myself (without reconfiguring my computer's settings), since I have other Ansys products also installed, and it behaves probably differently when compared to computers without other Ansys software installed (i.e. computers of our students).