Disregard - problem solved. Thanks!
Unless you named it something specific at the time it was set up, it's likely just named "jamfsoftware" That's the default name.
Outside of this, you should be able to see if that's the db name by going into MySQL command line and doing:
use jamfsoftware;
If that works, and you can see data by listing tables or whatever, then that's the name of the database. If that doesn't work or it complains it couldn't find that database to use, then it's named something else, but I think to find it you might need to look in something like the server.xml file on the JSS or maybe the database.xml.
For the benefit of others who find themselves in charge of an undocumented JSS instance:
If you have the ability to make direct MySQL queries against the MySQL instance, run the command SHOW DATABASES; . If not, connect to the existing JSS and look at the JSS instance database configuration file.
On macOS:
/Library/JSS/Tomcat/webapps/RootOrInstanceName/WEB-INF/xml/DataBase.xml
On Windows:
C:Program FilesApache Software FoundationTomcat #.#webappsRootOrInstanceNameWEB-INFxmlDataBase.xml
In the JSS web GUI go to --> JSS Summary --> Unselect all except at the bottom for Database (select all) and then Create. The database name should be under the section with MySQL. example:
Database Type MySQL
Database Driver .................... org.mariadb.jdbc.Driver
Database Server 192.168.0.55
Database Port ...................... 8406
Database Name jamfsoftware