You can try to install GTM, which might help you get a custom install of FB pixel: https://www.3whitehats.com/knowledge/shopify-enhance-your-google-analytics-install-gtm/
If you don't want to use Shopify's default Facebook pixel setup, then you have to do it yourself and the best way is through Google Tag Manager.
However, coming back, why are you even looking at an alternative solution. You said "people are able to manipulate my pixel and show crazy results on my adsets." What do you mean?