This study makes no predictions.
This study and others like it suggest that the nucleocapsid antigen is the most likely trigger for potential problems with immune response. Further, this study in particular specifically suggests targeting the S protein by itself:
“In this regard, animal model studies with FIPV in cats and RSV in mice have indicated that viral surface proteins may be the sensitizing protein of inactivated vaccines for immunopathology with infection. This suggests that presentation of the S protein in a vector format may direct immune responses in a different way so that sensitization does not occur.”
This was one of the reasons Pfizer, Moderna, J&J, Novavax, and others chose to target the S protein specifically.
In other words, the vaccines we’re using today in the US do exactly what the study you link suggests is the safest path. So you should be happy about that.