Well, since it's someone else behind the production they can't influence that too much, however if things go wrong I'm sure they'd either look for other means to get it done or refund the money. (I don't mistrust them in that regard)
As for the lack of updates and not replying to mails, that's a no no. I know they've been extremely busy lately, but that's not an excuse.
Well actually ZFrontier should be able to have an influence on this. They should be the ones steering the ship and making regular checks on Elemento and not just allowing to do their own thing. Especially when they find a manufacturer and then it becomes evident that the manufacturer can't do the work. At this point if I were ZFrontier I would be managing Elemento on a weekly basis, if not more frequent as they are dragging the ZFrontier brand through the mud.
Imho the ZFrontier brand is as good as it was before this gb, after all this is still a GB. Let me cite from
"What is a group buy? Should I join one? Group Buy FAQ / Buying Guidelines": "And it takes months, sometimes a year+ for group buys to complete. Be prepared to wait."
This is a more or less complex product unlike some keycaps from GMK i.e., where you gather money, give it to them and the rest will be fine. Here you have to work with not one but several manufacturers to get a complete product and if one thing fails the whole product is on hold. I for one account for problems to occur in such a gb, in the end there are lots of humans involved and everyone can make mistakes.
For the communication part i totally agree that this could be better, emails only come after many complaints here which is on the outlines of OK^^... but everytime they fail an expected date they should notify us before we start to "cry". Whom to fault there? Idk, ZFrontier seems like the party who handle the money part to let us feel more secure (assumtions!!! but imagine we wouldn't have ZF and would have given the money directly to Elemento, that would have worried me) and about Elemento i don't know nothing... maybe they have lots of work with other gbs, maybe it's just one human doing this as a hobby besides a 10 hour day job and caring about two kids.
TLDR: keep calm and clack on and to elemeto/zfrontier: more updates please <3