Hooking function when other addons are using local copies of it

[vaindil]

I use an addon that calls hooksecurefunc on TaxiRequestEarlyLanding. I also use a UI addon that replaces the Blizzard button that actually calls that function. The UI is using a local copy of the function, so the hook is never called.

What's the correct way for this situation to be handled? ElvUI does the same thing as the UI that I use, so I assume using a local copy of the function is fine. How is an addon supposed to hook a function when other addons may not trigger the hook?