I have one location, and one service, and this service is connected to one worker out of the total of five (5) workers.  There is one connection.  EA asks me to select the employee which makes no sense since the one employee is already setup in the only connection to the one location and one service.  After selecting a worker, it does not matter who you select, nothing else happens.  Here is the shortcode...  <div align="right">[[ea_bootstrap min_date="+3d" max_date="+3w" show_week="1" layout_cols="2" location="1" width="800px"]]</div>
I have also used just [ea_bootstrap] with no difference in how EA behaves. I also had 1 location, but 5 services each with one worker in each of 5 connections, but this did not make a difference either.  The one service has duration of 30, slot step of 10, and a block after of 10.  The 1 connection has slots of 1... :)
This is the website if you want to look at it.... https://mod2.techniproedu.com/school-set-an-appointment
The website is not accessible from any menu selection, but it is public.