I am willing to bet all what's left of my BABA and DIDI stocks that the WS-15 will NOT go into a plane designated as J-10. I'll use '4th' to mean '5th' generation in this message to match the audio.
I replayed the clip several times. Based on the wording of the audio (good/literal/exact translation a few messages ago), it specifically said "for 4th generation heavy and medium combat aircrafts". J-10 doesn't fit at all. This being CCTV, the precision of the wording can be taken seriously. The phrases 'medium' and 'combat aircrafts' seem to rule out UCAVs and the H-20. '4th generation' rules out any next generation fighter due by 2035.
Like that AVIC half-second video clip that first hinted at the J-20S, is it possible that this video announced the existence of a near-term single-engined 4th generation fighter project based on an existing design? A plausible explanation is that the J-10D or E will be sufficiently different to be given a J-2X type designation. Not too far-fetched as there is a precedence. 'Shandong' was given Type 002, not Type 001A.
And also based on the wording, I don't think we can expect the WS-15 any time soon. 'Made major strides' means it ain't ready yet. However, the video itself conveys confidence that the worst is over.