IFG Zakat Portfolios - Topping up with "Peace of Mind"


I just wanted confirm something about the charity portfolios if that was okay and how the Zakat calculator works.

For the Peace of Mind Portfolio, the strategic NGOs that are non-zakat eligible are included. On page 15 of the charity guide it says:

“If you would like to give to these charities you can just top up your zakat with some sadaqah
and allocate to them that way.”

If I were to give £100 zakat for example, my understanding of this line was that if I do not top up with Sadaqah, then the non-zakat eligible charities would be excluded from the £100. If I were to top up with £10 sadaqah for example, then It seemed to me that the system would process that top up of £10 and distribute as according to the portfolio.

Similarly on the “charity allocation page” it mentions:

Please also note that the following organisations are strategic NGOs and should be supported with your sadaqah (top-up) money: 5 Pillars, MRDF, Islam21C, MYH, and MEND

which seemed to imply something similar.

However the fine-print on the same page stating:

“You can still give to this portfolio if you adopt the stricter opinion, you would just need to make sure 13% of your donation comes from sadaqah.”

This indicates to me that this portfolio should not be selected if my contribution is 100% zakaat. I am assuming that 13% of this portfolio allocates to the non-zakat eligible NGOs such as 5 pillars etc .
In this case the donation would be as follows:

Zakat owed: £87.00
Sadaqah top up:£13.00
Total £100.

Without the top up this portfolio would allocate 13% of £87.00 = £11.31 to the non-zakat elgible charities correct? Which is why the top up would be necessary to ensure the full zakat contribution is made properly. Is this understanding correct?

For now I will select the other portfolios, but I just wanted to clarify, whether I understood this correctly.

Jazakallahu Khayran