salaries on abroad employees

i need a clarification pls help me.
Our client company is located in a sez unit .it is a sister concern of a abroad company.Abroad workers from parent company are working here.butin pay roll of this sister concern,thier names are not included. but the company gives them some amount as allowance to go thier country thrice in a year.they accounted this amount as vocation allowance under emplyoee cost. is it right ?