The odds of successfully finding all required data to complete the web of evolution is factually 0%. While large fossils exist fossils of microorganisms are rare and few and far between often destroyed even by accident. To make matters worse even large organisms are rarely found whole making the tree at best a series of wonderfully scientific guesses.
Macroevolution is a whole different bag. When discussing actual science, certainty is never on the menu.
For someone to demand certainty from a science is foolish. This person is either ignorant of the system, or seeks to undermine the system by misrepresentation.
We can look at the data provided and make excellent theories (no, not guesses, opinions, or spitballing) as to how things became the way they are.
Creationism has plenty of evidence against it. It lacks any semblance of being possible or realistic, and with this is mind goes the OPPOSITE direction of evolution, of which is only gathering more supporting evidence as time goes by.
Simply find an organism which as anachronistic to the timeline which the theory of evolution predicts. For example, find the fossilized remains of a rabbit in the geological strata which hold the record of the precambrian era. Do something like that, only once, and the theory of evolution is dead.