slow dry is a good thing. if it is too wet to be in a ncontainer, don't try to force a square pag through a round hole (where D = L). All that will do is potentially grow mold. 75% is too high for long term context.. short term is less worrying. So, take them out.. dry longer, and try again later.
The hay smell will go away, if you didn't speed dry it, which is the case by your description.
If possible try to keep drying temps under 70Ff, but sometims you simlpy do what you can do and not fret over what you are unwilling to do or invest in.
is that mold or a nug out of focus in that picture?
Also, stems cracking is more art than science. it can be a good trigger, but be consistent with the size of stem you try to snap. I fidn that at the point it feels dry and light, it needs 12-24hours longer drying before put into cure buckets, or else i have to pull them out for some extra dry time. I want the last few percent of unwanted portion of water-weight gassd off in cure buckets but not more than that
if your temps, rh and conidtion of buds (wet trim or not, on stem or not) are consistent, then it should take a very similar amount of time -- common sense applied. i.e. if the buds are denser give it slightly more time than normal.. or fluffy it needs less. you'll find familiarity if you keep track of it.