"This is the invitation to the conference, but it is in Japanese."
Translation:זאת ההזמנה לכנס, אבל היא ביפנית.
There is a small difference, but both should be accepted in this case. Usually KENES - the something much bigger (think of Knesset). An international conference will be KENES. However, VEIDA is also correct when it is a smaller event. So here it was impossible to know.
In hebrew we usually use both KENES and VEIDA regadless the size of the meeting, hence both are correct and you won't be wrong using each one