Depends. If nothing else Psychotria is a great teacher of patience. Under ideal circumstances and genetics I can get a 6 inch tall plant in six months when propagated by leaf cuttings. Others can take more than a year to get to that size.
I usually start with an entire leaf because I find it speeds things up. Greater leaf surface area means faster growth of the plantlets. Since yours are half leaves they will probably take longer.
Excursions up to a temp of 90F won't necessarily be detrimental, but if you could keep it to the high 80s I think that would be OK.
And just to be clear. I rarely have Psychotria leaves rot at temps even well past 95F, but I have gotten reports of folks up north having problems with them. Don't know why that might be the case, but apparently your latitude can affect how these things go.
I already asked Alice.