Scatter and Line Chart using same x axis?

Good Morning everyone, hope you're all having a good week so far. I apologize if this is something that's been asked before, but in searching the forums I did not find anything similar to what I was looking for.

I'm trying to create a combination of a Line and Scatter plot. I'm putting together a correlation between Average Speed of Answer and Service Level in a call center.

Ideally, the X Axis would show Service Level (descending from left to right from 100% to 30%, where no data below 30% exists in the data set), and the Y axis would show the Average Speed of Answer in m:ss format.

The Scatter portion would display all of the raw data points from two years worth of data. If any day (FYI there is no date information in this chart, each day is considered equal for the purpose of this exercise) showed up at A Service Level (x axis), it would be plotted at B Average Speed of Answer (y axis).

The line portion would display the mean average of all of the ASA's at each individual SL%.

Visualizing it in my mind, I know I could manually draw this in one graph. Both the Line and Scatter share the exact same X and Y axes, including upper and lower limits.

I cannot for the life of me figure out a way to force it all on one graph and one X axis without A) plotting the Line or Scatter on a secondary axis or B) the scatter portion being thrown out of scale so badly that it's all against the Y axis line at 100%.

EDIT: The reason I want to force it all onto one axis is because then, I can add an additional set of data (how Abandonment Rate and Service Level are correlated) that definitely uses a different Y axis even though the X axis would, once again, be shared.

I've uploaded what it should look like (when I use a secondary axis), what it actually looks like (when I try and force the same axis) and the data associated with it.

Thank you all in advance, and have a great rest of your week!

I am not sure I understand the need for a scatter + line combination chart. When I do similar things, I just use a scatter chart for both series. The raw data series is formatted as "markers without line" (through the format data series dialog) and the ":average" data series is formatted as "line without marker". It should be as simple as selecting each data series -> Format -> format selection -> Choose the appropriate marker and line options.

Am I misunderstanding something?