K fare clarification
 

K fares earn 100% RDMs and 100% EQMs on United metal but earn 0% RDMs and 0% EQMs on all partners, etc. Is this correct?

No, it depends on the partners and routes, every partner is different. Like for NH it is 100% RDM and 100% EQM in K class for flights between US and Japan, within Japan with an international connection, intra-Asia (excluding flights between Japan and Australia, mainland China or India, HKG is not included as mainland China), but the rest of the NH routes only earn 50% RDM and EQM for K class.

Why not just check it yourself instead ?

https://www.united.com/CMS/en-US/mar...ePartners.aspx

A key issue is the fare class of different airlines are different.

A "P" fare on AC is economy but on UA is discount International business / domestic first class.

The fare class structures of airlines vary. In the case of codeshares, the marketing airline uses its fare structure but for mileage credit you need to know how that maps to the operating airline fare class. That is not easily obtain and best found by call the operating airline after ticketing (unfortunately).

Once armed with the operating airline fare class then use the link provided by ORDnHKG to determine earning. It is true that many airline operators are not providing miles for the deep discounted fares, presently UA is still 100% earning for the flights it operates.