In my experience, it's better to use pure SIF to install Sitecore. SIA does not surface all configurations in the GUI, which won't work for all use cases. In those cases, you'll need to make manual changes to the underlying scripts anyway, so again you may as well take the time to get a good boilerplate config set up with SIF that you can easily modify and reuse later.
I'd start by doing a full uninstall and manually check that everything has been uninstalled:
- Databases
- Hosts file
- IIS
- Certificates
- Indexes
- Services
It's also a good idea to restart your PC after you do this.
This could also be a problem with the underlying install scripts. Pay careful attention to the install logs and compare the successful database creates and authentications to this failed one. What exact connection string is being used to authenticate into sc10_Xdb.Collection.ShardMapManager
? Does it match the same connection string as the other DBs?