Migrating SharePoint 2010 site collection to SharePoint 2013 existing farm

Hi All,

We are currently planning to migrate one of our site collection from SharePoint 2010 on premises to the already existing SharePoint 2013 on premises  by database attach and detach method. Following are my queries

1. I have read various posts regarding the migration to a new farm but in my case we are migrating the Nintex database  to the  farm with existing Nintex database .Is there any helpful post or the steps available so that the existing data on SharePoint 2013 farm wont get affected?
2. Can we just migrate the Nintex content databases  or we will need configuration databases also? in this case can we split the configuration db?
3. Vadim Tabakman‌'s reply to the post https://community.nintex.com/thread/2479 seems useful for my situation but I need some clear approach.

Cassy Freeman‌ Eric Rhodes‌ Andrew Glasser‌  Vadim Tabakman please suggest