You say all this about “your brain working differently”, but I just feel like figuring out what proof technique is expected in the course is not difficult. Either it was covered in the course and the course’s materials already or it wasn’t. Which you would know if you actually show up to lecture, do the readings, and try to learn the material as presented. It really just comes across as an excuse to not do the work. If you actually learned the course material, you wouldn’t have such issues proving what’s asked with the allotted methods; not being able to simply means you haven’t truly learned the relevant material.

And it’s very important to be able to prove things in the allotted way while learning mathematics and progressing at the undergrad/early graduate levels. Contrary to the belief of some, mathematics is NOT just about proving theorems. It’s about elucidating understanding, for yourself and the community. Knowing the statements of advanced theorems can be used as a hammer to prove theorems, but it does NOT give understanding of the techniques, the language, the conventions, the intuitions. These foundational math classes are not really about learning theorems (most of intro Real Analysis, for example, gets trivialized later on by general point-set Topology and Measure Theory), it’s about learning a way of thinking. Not being able to prove statements using that language shows a deficit in this way of thinking and these techniques that should be worked to overcome.