I goofed my WP accounts and registered domain funny. Help?

I have a personal blog that I’ve used for years and my husband just started a business. I went to claim a domain for him and managed to claim it under my personal blog. I was able to make my old wp.com url the primary for the blog, but now I need to get the domain from my blog to the new wp.com site that will be my husband’s business site?

Any ideas? I would hate to transfer to a diff hosting just to transfer back… Especially if it will cost $$.

Shows blog and new domain purchased:
https://www.flickr.com/gp/136161462@N07/68Ga03

Shows all 4 blogs i have with nee blog i need website on…
https://www.flickr.com/gp/136161462@N07/E7A0a6

Thanks!