Piazilla you sound like a very level headed young woman and I totally understand about your overbearing MIL (I had one of those once!) and as you say 2 very different cultures involved. You seem to have found a good compromise.
Incidentally I think you may over time need to find a way to "stand up to your MIL" and that doesn't need to be in a confrontational way - there are ways of making your point tactfully and I think if you could do this, you would feel a little more empowered with your MIL. I understand why you don't want to leave LO with your MIL because of the strong pain killers, but couldn't help a smile about a bit of honey on her finger! That's honestly not going to do him any harm. I remember my MIL and FIL putting bits of milk chocolate on my firstborn son's tongue at the age of about 6 months, and of course it just melted. I didn't want them to do this (but it was done a lot in those days) but I bit my tongue (just about) but they knew I didn't like it and was a bit fussy over what he ate. I found an old photo recently of my son sitting on FIL's lap on the garden swing (he was about 1 year old) and he is holding something. I thought it looked like a chocolate bar but DH said it was bread, so I had the old photo enlarged and it was a chocolate bar!! We both had a good laugh and of course it never did him any harm. Mind he still loves chocolate and almost 50!
I think it's interesting how so many posters have come on telling you not to go and not to do this, that or the other, even though you have made your plans clear. I think this is what I find so insidious about these MIL threads, the way all these other women come on with their advice about what to do, and some of the posts/advice is so spiteful. Why can't you women just accept that the OP has made her decision. It's almost like you can't bear the thought of this MIL being given the chance to see her grandson. Sorry but that IS just spiteful - there's no other word for it.
Randomess I think your post epitomises all that I dislike about MIL threads. Your advice about what the OP's DH should say to his mother, and the manner in which you suggest he does it, sounds exactly like an adult talking to a child. SO dreadful........and I find this is not at all unusual. I don't know if you have a son, but if you do, I hope when it's your turn your son does not talk to you like that - NO on second thoughts I hope he does. Then you will know how that feels.