There isn’t any way to split the row in ACF. It’s one of the negatives about using tables. You could probably do this if you wanted to add custom JavaScript and custom CSS to the admin page, but it sounds like a lot of work. http://stackoverflow.com/questions/25405105/break-a-table-row-into-multiple-line-responsive-layout
With something like this it would probably be best to use either block or row for the repeater layout. With one of these you can alter the width of each field so that there are multiple fields on each line by setting the width to 50% or 25%.
