ASN Chart, page-3667

I think you’re looking into it too much.

The brine (LKE also) is made up of dozens of minerals, the advantage of ASN brine is 4 minerals have a commercial value. The DLE tech stays the same, it’s designed to extract lithium only regardless of other minerals. The tech for the other minerals appears to be relatively simple and has been used for many years. It’s only the DLE that needs refining because it’s new.

In regards to Lilac, their tech extracted 75-80% of lithium from memory, essentially rejecting 1 tonne for every 4 or 5 tonnes produced.
ASN found a new tech provider with 91.5% recoveries, of course you go with the company that makes you more money.