Using a tab control like this and a layout based on Companies, your employees tab would need to use a portal to employees if you want to scroll through a list of more than one employee. The default format for a portal creates a tabular view of the data, but this is not the only option. You can reduce the number of portal rows, resize the portal row and thus create a kind of "mini form view" where you can still use a scroll bar to scroll through multiple employees.
There are also ways that would enable you to place fields from an occurrence of employees directly on your tab panel with scripted buttons that control which employee's data currently appears on the tab panel. This creates a different relationship that matches by employee ID and scripts that manipulate the value of that match field in your company table.
Another approach would be to base your layout on Employees. Assuming that any employee record is linked to only one company record (something that might not always be true...), You could then show the data for a single employee inside your employee tab panel and pull up any employee you wish to see by navigating to a different record--something that can be done both by moving from record to record, performing a find, or using your own automated methods driven by controls that you set up for this purpose.