Hi Brett,
There is no way to force it, but if you can be patient, anyone is allowed to complete a merge 30 days after it was suggested. Here's the full explanation in our Help pages: What can you do if you're waiting for approval from someone else?
Propose the merge, Wait 30 days, it will then be approved for merge by default. You can check the status of your proposed merges. Upper right corner "Find". Drop down menu "Pending Merges." At the top of the page "Pending Merges Initiated by me"
For help merging
http://www.wikitree.com/wiki/Merging