In my honest opinion, Zayn has a much better chance at WR than anybody else on Earth, and people overestimate YiHeng's 2x2 skills...
I tried the 0.93 scrams and got 1.45, 1.47, 1.75, 1.77, and 2.39...
Even though I know EG, I turn really slow, and I could easily see how good the scrambles were. YiHeng just used pure TPS and luck in order to get this average. In fact, he gets quite a bit of Low 2/High 1 averages, showing that these scrambles were clearly lucky if he managed to get Sub-1.
A few of my friends who avg 1.5 on 2x2 got 1.0x averages on these scrams, showing that if top 2x2ers got these scrambles, many would easily get Sub-1. In fact, my friends who are 2x2ers get Sub-1 averages often.
It is just a matter of time and luck before the Sub-1 barrier is broken, and Zayn is the one who is most likely to get it. His solutions are the most efficient and Zayn has many Sub-1 official fails. Namely the +2 out of 0.97 (iirc) and the cube drop that happened which likely costed him WR.
On the other hand YiHeng's case is more like Luke Garrett's. He does the same solutions as me, but just turns way faster. YiHeng likely averages 1.5, and if he does it again, the scrambles are likely insane.
So I do not think that Zayn will need to get stupidly lucky for Sub-1, but YiHeng will. (Contradicting your statement).