Ok so I looked everything over yesterday a few times, and this really looks doable for me. There are a few of the more “technical” looking runs a month+ down the line that I will have some questions about, but I’ll wait until we get there for that. The only thing I’m seeing is that my 5k in July is on Sunday the 4th, not Monday the 5th.
I thought it odd when you said your July 4th race was on July 5th. I've fixed that for you. In order to make sure things stay good on the ramp rate, I've included a 1.5 mile WU prior to the 5k. I think this will aid in performance as well.
Question: can my SIL, who is much faster than I am, also follow the plan using HER pace chart, or will she not have enough training TIME in since she would complete things much more quickly that me? Idk what her summer run plan is at this point, so I’m NOT asking for you to re-work it for her paces.
Yes and no. If she interprets the plan as written in terms of time, then she could do the plan at her paces. For instance on 6/24 and 6/25, you're scheduled for 3 miles EB and 7 mile LR. If she were to do 3 miles EB and 7 miles LR at her paces, then this would be an insufficient workout. But if she instead, looked at the "Easy" and "Hard" time columns, she would see the 3 miles EB is scheduled for 40 min and the 7 miles LR is scheduled for 91 min. So if your sister did 40 min at her EB pace, and 91 min at her LR pace, then it would be a sufficient workout. When I write the plan, I write it based on effort and time. The calculation to determine mileage is simply for the end users (you) preference as most everyone prefers mileage based plans. So for 95% of the plan, it could work for her if she interprets time and not mileage. Workouts like 7/9 are also easily convertible for her, but take a little more time to calculate:
3 mi @ WU + 8 x 5 min @ T w/ 1 min RI @ WU + 1 mi @ CD
So the 3 mile WU is 45 min of easy pace, then the 8x5 min workout with 1 min rest is easy for her to do the same because it's already written in time, and then a 15 min CD.
For the R pace, you can see that 100m R is 36 seconds, 150m R is 54 seconds, and 200m R is 71 seconds. So she would just focus on those durations rather than the distances. The workout was written with the idea of trying to get reps of ~30, 60, and 75 seconds of mile pace.
At the end of the day, it's doable with a little leg work on interpretation. However, if the scheduling system or amount of time per day is not something that works with her personal schedule, then just let me know. I can easily write something that is specific to her from the ground-up and not based on your schedule.
Fingers crossed that it’s a short lived phase. 
