Hi {user:Queen NormaJean is cheering},
I went to the National Library of Medicine - National Center for Biotechnology

and found a very intense article. I've been through it twice, but still want to dissect it again. I did copy the overall conclusion to share. Very interesting. I am giving you two addy's in case you would like to read it:
1. https://www.ncbi.nim.nih.gov
2. Simon, G. (2023). Detection of Fatal Potassium Overdose: A Case Report and Review of the Literature. Diagnostics, 13(7)
https://doi.org/10.3390/diagnostics13071339

Here is the Conclusion of this report:

5. Conclusions
The threshold of lethal potassium dose is around 15 mEq for intravenous and 300 mEq for oral overdose, but in cases of oral overdose, even much larger doses reaching 1000 mEq can be survived if treated in time. The threshold for lethal potassium blood concentration is 9–10 mEq/L.
Because of the factors described above, it can be stated that the potassium level at the time of death cannot be assessed reliably by the post-mortem potassium level of different body fluids [2,61,62], so post-mortem biochemical analysis has only limited diagnostic value in potassium overdose cases. The best feasible way to prove potassium overdose is the collection and analysis of circumstantial evidence, which underlines the importance of accurate death scene investigation.

Kristina

P.S. If you come across any more questions like this. let me know---OK?