Are service dogs allowed in the park?

Yes but its not walmart, they may ask you for proof and if it becomes a pest or nuisance tàthey may ask you if you could remove it

Yes, All Service Animals w/ a vest on saying " please don't pet", some are very preticular Service Animals. You must also have the Service Animals Permit, but you can take your Service Animal Anywhere though.

Yes

yea, I've actually seen an employee (tram tour guide) with a service dog.