Firstly, I would ease up on the amounts that you are using. When you are buying these craft soils they are generally aimed at having the target nutritional levels required for a complete run. Unless you are building your soil yourself, the frequency of top dressing you are following is a bit too much in my experience.
I do not think that is the issue though. I don't think that its a toxicity issue. If you were feeding it nutrients directly or something soluble then I would understand but adding too much organic material that is high in N is going to result in toxicity. If you look at the soil food web, root exudates are the base for all of what gets broken down and they are controlling the biology in the soil. If the plant does not need N, it will change the exudates it releases to feed the biology it needs to break down whatever nutrients it wants.
Secondly, cannot be a deficiency in K based on my first line here. These soils are loaded, not a deficiency.
Its nutrient burn. The outer yellowing and the brown tips look like nutrient burn to me. I think that there is something that you are doing here that is causing an issue that is not in the information given. Are you doing water only? I know that compost teas can cause these types of problem but I am really not sure how you are getting the problems suddenly other than there being something that you are doing that is triggering an imbalance. I feel like its got something to do with the first top dress and the tea you gave the plants that started something in the soil that lead to the problems you noticed on the 5th.
I would not throw any more nutrients in the mix. If you think its potassium deficiency just get you hands on some potassium silicate and do it as a foliar spray. That will give the plant access to potassium immediately vs it having to be broken down in the soil. That will be my next step if I think its a Potassium deficiency, which I don't think it is but yeah do not add anything more into the soil.
Lastly, you do not have to ph your soil when you grow in a Living Soil system. The soil will do that for you. The reason for doing it in a salt based system was to ensure that the ph was in the right range for the nutrients to be taken up. Water carried the nutes to the plant for you in synthetic systems but in soil systems it serves a different purpose.
A bit of advice here, take 2 steps back rather than one step forward when you are growing in these systems. Its not like synthetic systems, you cannot just flush out an issue. Rather come here and ask a question vs diving into adding things to solve a problem. It is going to save you so much time and energy. Trust me on this. If you really want to get really good at this technique realize that is extremely complex and takes time to understand. No point crying over spilt milk so take the mistakes in its stride.