I'm not sure if this would be an issue in a somewhat older Honda, but
my 2000 Integra will lock its shift cable into Park whenever, for
example, the horn fuse is blown or removed, presumedly as a safety
precaution (I found this out the hard way while rewiring and testing my
Acura alarm system).

I admittedly know very little about Honda's electrical systems, but I
thought I'd throw this anecdote out there in case it might serve as a
starting point in your investigation. Good luck!