@Lazerus00 hmmm 6.2 aye? Kinda surprised there. Guess that's the bottom of the range for soil right? 6.2-6.8. Though your issue is not low pH as you'd have the edges curled up as you had last year:
https://www.thcfarmer.com/community/threads/tnelz-thread-about-whatever.66628/page-70#post-1436533
Definitely wasn't expecting overwatering or compaction; just was relaying how I'd sort through it.
No matter what (unless in a state of adaptation); growth is limited by liebig's law of minimum. (which includes 6 factors affecting plant growth and yield; : air, water, light, temperature, soil or media and nutrients).
If we are to assume that air, water, light and temp are correct; this just leaves medium or nutrients. With the medium we can look at moisture, porosity, saturated air percentage, pH, pathogens. Otherwise we are left with nutrients.
With nutrients, organics are often separated from chemical relative to availability or speed of availability. Organic compounds being more complex tend to take a bit more time to be uptaken or are uptaken at a slower rate. However salinity as a whole still relates to osmotic pressure; which affects transpiration. To these ends;
http://plantsinaction.science.uq.edu.au/edition1/?q=content/17-1-3-solutes-and-osmotic-pressure
"The osmotic pressure of a solution can be calculated from solute concentration per litre (or per kilogram) of water . With organic compounds such as sucrose that do not dissociate into ions in water, osmolality (osmoles per litre of water) is the same as molality (moles per litre of water), which is almost the same as the more familiar term molarity (moles per litre of solution). At 100 mM, the discrepancy between molality and osmolarity is only about 1%."
http://www.zobodat.at/pdf/PHY_18_1_2_0071-0078.pdf (test done in outdoor soil)
"The results obtained indicate that the plant salinity and osmotic pressure values changed linearly with changes of the salinity and osmotic pressure of the soil. On the other hand, the loss of water by the transpiration of the plant decreased with an increase in the salinity and osmotic pressure of the medium and plant."
So Increasing salinity, increases osmotic pressure which decreases transpiration. Just like with salts and EC; differing compounds have differing osmotic pressure coefficients, so are not specifically the same. However, in all cases a higher solute concentration will have less net water transpired vs the same solute at a lower concentration. While an organic nutrient at XX concentration is less likely to burn; it may well have a similar OPC (osmotic pressure coefficient) and thus alter water uptake similarly to chemical.
I don't know that flushing works the same in organic vs chemical as an increase in moisture will also net an increase in new compounds available. I know it's generally not done and I would not have experience to suggest here. Though your plants have already gone through the adjustment period; so it is most likely a matter of time for them to get the salinity down and increase growth. Again I would watch for more of the S- as it directly limits N uptake (the largest growth contributor), but would still hesitate to add it just yet.
Guess too plants have the tendency to show deficiencies of elements (that they otherwise would not) when returning to normal soil solute levels; from previous times of being high.