Seeking advice if anyone would have had a similar experiance on a rather unique case? (2 tickets)

Ticket 1 : YYZ-JFK-ICN (marketed by KE, operated by DL for YYZ-JFK, and then KE operated flight for JFK - ICN)
Ticket 2 : ICN-PEK (marketed/operated by KE)

I have called both airlines for advice or a little bit of clarification, but so far stuck in the middle
KE : Through baggage check is possible, but it is up to DL as my first point of check in would be a DL counter
DL : 'should' be possible, but there is no guarantees as there are no cases in T&C

As per T&C, I am not sure if my 'code share flight' from YYZ-JFK counts as a 'delta ticket' in :
"Delta ticket plus a ticket that includes one of the following Delta partner airlines, as long as the flight is "operated" by that airline:"

While I do not mind re-checking my bags normally, my connection time in ICN is 1.25 hrs (MCT in ICN 45 min)
→ Wether DL being able to check my bags to PEK determines the possibility my second itinerary