I was the same and cannot drink milk, however there is milk already in the packs and to be honest, adding soya milk or normal milk to the packs just made them a little creamy, they didnt taste milky at all. I used full fat milk then you just have a little added to each shake and water it down as much as you like.
Just give it a try the day before your meeting and if you really cannot stand it then speak to your LLC and they will be able to help. I was advised that maybe I could have a little cheese or someting adding up to 500 cals a day, however that really is a last resort as at this early stage you really need to stay 100% ss as you can so very easily fall off the wagon having done so well for all these weeks, amazing that little bit of food can be an absolute disaster to all your hard work.
Good luck, hope you like it (or can tolorate it) in the end.
Lisa xx