Attempting To Use Goal Difference As Tie Breaker (Possibly Using IF?)

Basically it is another sports modelling experiment that I have had (I get the day off work and come up with things like this ), where I just had a curiosity to play out the last games for the top 3 teams in the English Premier League (just to see if I could get some percentages).

The attached, is just the values from one run of my model (I have taken the workings out to reduce the size and for other reasons).

Basically everything to the left of column K, is the model and I am happy with it (and I know goals have to be integers - this is basic);

This plays the games out, and feeds the data into the table at M36 (highlighted yellow), which feeds the data tables at M42 (highlighted green), which are counted to get percentages in the tables (highlighted yellow at M6).

I have put some example output from runs on the second worksheet (so you can see how it works - I like that it suggests Chelsea can win even though it won't be very likely )

Basically you can probably see the problem in cell O22. The percentage chance of finishing first should equal 100% when totalled (e.g. the sum of Liverpool, Chelsea and Man City finishing first, as it has to be one of them should equal 100%). I tracked this back to the fact that I had no way of splitting teams level on points. As a result I added Goal Difference to the model (crudely - e.g. decimal) and here's the question;

How would I go about using Goal Difference to break tie's effectively?

I am thinking I could do some kind of IF function in Q37 (and then have a tie-breaked rank in column R to feed the data tables), on the basis of if anything in N37 to N39 was equal but I am not sure how I would go about applying this.

Example Values_EPL.xlsx