Well, the causative form is basically used when you want to say that someone did something for you. It's also a way of rearranging your phrase to highlight something you may want to emphasize, kinda like in the passive voice. For example, the sentence "he got a fish hooked" puts less emphasis on the person that hooked the fish; Notice the difference in the sentence "he hooked a fish", which highlights the subject that hooked the fish. Here you may find more information about the causative form: https://www.ecenglish.com/learnenglish/lessons/the-causative Hope it helps!

Yes, you can say it either way, but the phrase is slang. And anything from the series Friends is full of slang. So what you hear may not necessarily mean what you think it does. You would need a native to explain it for you, as hooking a fish can be the literal meaning , or have slang meanings..

Yes he could, and I think because it is from the television program/programme "Friends" he is referring to being successful at having a date with someone. Although I do not know the episode.

I hooked a fish. I got a fish hooked. . Equally valid.