When creating a Facebook pixel, Facebook provides information for a couple of types of implementation:

In the first option, "Use an integration" they provide a plugin for:
When using either of these, WP Rocket no longer replaces the files.
See my comments on the Wrike card to download the zip files.
Those two plugins separate the init code (fbq( 'init', 'app_id' )) and the call to https://connect.facebook.net/en_US/fbevents.js into 2 script tags.
Our feature is based on the assumption that those two things are in the same tag, that means I'm really not confident of being able to make it work, I'll have to rethink the whole thing :|
OK I have a working solution, but it's really because it's you ^^
It almost works! There's a 404 but might just be as simple as a typo?

Dunno if it's related but I get this notice in debug.log
http://snippi.com/s/t4blnmu
Typo: fixed.
PHP notices: I had the same, they are not related to WPR.
Thanks for your tests @webtrainingwheels.
It's working for these Facebook plugins now. Thank you @Screenfeed !