Had to Go,
I'm sorry you have to go thru such a thing. I have to say that comments made regarding your conscience are correct. It is up to your conscience. If what you are doing requires in any way that you give some act of worship other than God, (Jehovah) then of course you would know already that it would not be right, but we're just talking about a wedding. It is a time of Happiness and Rejoicing.
I think of Jesus when he sat and ate with Tax collectors, and all your doing is rejoicing over the Marriage of a family member, whether it is in a church or a Hotel.
When you said the phrase "dedicate yourself to Jehovah", a thought comes to me. Many years ago, the 2 questions they ask about baptism at the assemblies initiates the thought of dedicating yourself to Jehovah, now they use the phrase "dedicate yourself to the spirit anointed organization." I know that in your heart you probably worry about whether you are offending HIM, well look at the whole picture, are you breaking any scriptural laws? I would say "Not in this situation".
I would not judge your husband, but I can understand that same mentality that I had when I was in the organization. Everything in our life was always marked with the stamp of "Organization Approved" or "Organization does not Approve". It was their Rubber stamp that they would use on whatever you chose to do in life. Thankfully, I worship God without their help. I hope it will all work out for you in some way without the pain.
Happy Trails!! Truth and Justice