They all only slightly differ but if they were exactly the same, you would say that they’re just copying one another.
The fact they aren’t exactly the same gives it more credibility.
not it does not, for instance they don't even agree on the day of crucifixion mark and john don't even agree on the day(matthews and lukes are just embelished from mark)
that is a crucial disagreement for such an important event
they all differ in how jesus was at the time of his death, in pain(mark) special effects kicking off everywhere(matthew) calm(luke) and bullish giving it large(john) no credibility at all
and that's just that supposed event