Hi aasif,
Well there is nothing like believing which tool is correct and which one is incorrect. I presume that there must be some error which your friend makes while dealing with optigrating. As you know the equations are same in both the tools hence the probability of being incorrect of any of the tool is very small. I would suggest you to do exhaustive analysis on using it in optigrating and compare it with results shown by MATLAb. There must not be a huge difference.
Thanks and regards