How is that helping you bring you closer to the goal of co-parenting with W in a peaceful way? It sounds like you're assuming here with "ending up less than" full custody. From where I'm sitting, what your L is sending to W is setting up for an acrimonious dogfight with her. Is that what you want out of this process?
I would urge you to revisit your approach here. What DO you really want?
You cannot force someone to move back in your Province. However, you DO have something to say about sharing custody with the kids and the financial settlement. Focus on this.
My L suggested going with what I mentioned above. I agree that it may be setting up a battle but I don't see how that is going to be avoided at this point. That is partly why I thought I should send the email to her. (the other reason is I had told my W I would) If she will agree to the schedule, or at least come close to sharing equally, then we can go ahead and do all of the other financial things she's wanting and likely have very little need for L's at all. If she will not agree to it then that email will show that I have made every attempt to be fair in the sitch and it will show she has been pretty unreasonable.
Also, I can force my kids to be brought back to my province. It may or may not be successful. My W is currently living in an area with one of the highest crime rates in Canada. It is not a good environment for our kids to be raised to say the least. My W took our kids away from the home, family, friends, schools etc that they knew and loved to go to a very poor area with only the support of her elderly parents.
I'm not sure what my alternative would be? If I use the L, tell her to propose 50/50 with our kids off the start and give up any other leverage I have with the financial matters I think I'm taking a huge risk of ending up with basically the same custody arrangements my W has dictated as well as a big L bill.
Me-40,W-37 D7, D5, S3 Separated Oct 3/2013 T 11 YRS M 7 YRS