Debt obligations of Guarantor

My friend in the Philippines has been working as a Sales Agent in some type of jewelry business for another woman. My friend sold some jewelry to one of her regular customers but a large amount of money was owing by the customer and she has fled and her whereabouts are unknown. My friend was guarantor of that sale and now her boss is demanding via phone calls and text messages that she pay her 150K peso for the debt of the unpaid jewelry. My friend has been threatened that she will be taken to court if she does not pay but she does not have the money or any possibilty of ever getting such a large amount.
What action can her boss take?
Is my friend liable?
What advice can you give my friend?
My friend was due to travel outside of Philippines to visit me for a vacation in August will she still be able to do that?

the boss might file an estafa and/or a collection case
since she guaranteed the transaction then he is obligated to pay
she should try to defend herself in an estafa case by accounting for all the funds and the jewelry that she received
if there is no court order to prevent her from leaving she can travel