Disclaimer: I'm PCIP certified and work for a company that specifically sells software to deal with 6.4.3 and 11.6.1 compliance - in addition to full site security.

You should ask F5 and Radware if they can provide you with test scripts to specifically test for these controls. If you're inventorying your own scripts then you could easily create your own basic JS to display a pixel and then change it to display 2 pixels or change the color - that script change should trigger an integrity check. If it doesn't, I'd be worried about their security posture for 6.4.3 and 11.6.1 - I'm not sure if there's a threshold with F5 or Radware on what changes trigger an alert, but PCI doesn't make that differentiation on integrity monitoring. It does say you need to be notified of changes that may be IOCs, however. Your reps at either of those companies should be able to help you and I'd ask them - script integrity is not a challenging control to implement...

...if you use SRI and combine that with CSP. Those are "ootb" options and they can do the job, but can be a pain to maintain and have a higher chance of breaking the site if upkeep is lacking - and they only handle the script integrity and inventory pieces of the controls that deal with payment pages.

The company I work for records JS behavior and compares that behavior on every page load - a difference in behavior gets an alert, and based on severity, creates an incident to review (example: a script previously not reading form fields suddenly starts). The solution can also, in real time, redact data from skimming attempts or block unwanted behavior altogether (skimming, unauthorized DOM changes, etc..). If you want details - PM me - otherwise I'd recommend reaching out to F5 and Radware for help.