[cypher]

Minor scuffles are normal but any escalation is a cause for concern I think, I have to admit I've never owned a pair (too much of a worrier!) but I do try to take note of things that have been posted in the past by members who do keep them successfully, that does mean I can't add anything more from personal experience though.
I can assure you that hamsters don't get lonely when living alone, it's natural for them & given a little time to adjust to the change they will be quite happy.
An alaska would be fine but you do need to take care setting it up as it's such a tall cage to be sure to avoid any risk of falls.
You sound worried & obviously you can't monitor them 24/7 so it might be as well for their safety & your peace of mind to go ahead & put one in a temporary cage for the time being.