Hello excel masters.

Here is an excel sheet of a tennis match:
1.png

My question:
How I calculate the probability of getting 15-0 on Game #5 if my sequence is :
15-0, 15-0, 0-15, 0-15
0-15, 0-15, 0-15, 0-15, 0-15
15-0, 0-15, 0-15, 15-0, 0-15
What formulas should I use?
Any advice is very welcome!

Regards,