Disclosure and what classes as inadmissible evidence

Hi, there was a post from over a year ago about disclosure. Asking something again because the original user deleted it so it's hard to put the advice into context. Can any seasoned folk tell me?:

1. If I had a recording of the discriminatory statement, but due to being immediately fired I didn't download the Teams metadata, and instead copied it to a Notes app, would that be inadmissible? I'm concerned I now can't use the very core of my pleading, that "R said XY". Surely if I pasted it into Notes/Word it could look like I just made it up? PS the R likely knew he was being recorded because it was a workplace norm. R has denied such a statement was made, in the ET3.
2. At the time of the discriminatory statement I immediately text my partner saying "Can't believe Dave just told me XY." Should I use this too? I still have the time-stamped SMS.

+ how much do notebook, handwritten notes count? Thanks