Hi,
If vendors don't want bad reviews, they should practice good business. All they should have done is refund you and that's that. I have had hoyas in the mail for WEEKS and most of them arrived just fine. Only one died out of probably two dozen over several months.
I would let them know how disappointed you are in them, after having a previous good experience. I would tell them since they don't seem to accept any responsibility, you will be leaving a bad review. This has leverage with most sellers. If they still won't work with you, write the review. Paypal will refund you and go after them.
Some people are not trustworthy or fair. We've all been burned.