I think I should tell her to break up :(

My sister and her Bf’s chart for some reason scares me because of the Uranus, and Neptune contacts it seems like it will suddenly out of the blue will end and my sister will just end up hurt. Should I tell her? I know people say she should just follow her heart, But honestly I haven’t seen a relationship with bad Uranus stay alive or idk maybe I didn’t look hard enough. She’s my sister I don’t want to see her hurt. I just don’t think this is right.

But anyways tell me if I’m wrong about the charts. Because someone told me it’s unstable, or that one might cheat because of the Neptune and venus contacts and others said that it’s not unstable and that they won’t leave eachother because of the strong synastry, and others said there aren’t as they call “meant to be” aspects between them. ( but then again don’t some couples with “meant to be aspects” break apart?)but overall I’m just so confused on what to consider.

I believe you should look for vertex and saturn. Is saturn making good aspect venus? Also look for conj/opp moon/moon, moon/sun, they are excellent for long term compatibility.
But if uranus and saturn are making harsh aspects with venus, nothing can stop the relationship from ending. I and my boyfriend had venus conj saturn but we has a tight orb of venus square uranus with uranus in 5th of our composite and we broke up in a terrible way.
Look for the guy's vessus placement in his chart and for vessus aspecting her moon or venus. If so, it's a red flag. Best luck.

These are the charts actually not sure what to make of them