Well, without the "name calling part" I do recognise the frustration the trios can cause. For me the 4 trios I have been able to breed for have went in strange ways:
-Cosmic: It took a LONG time to get one of the animals. First was Lemurcury (after loads of fails), then another one of those, then finally Plutopus when there were only some 2-3 days left and then by some miracle the Caturn on the first attempt (a thing that has perhaps happened 2-3 times for me since starting playing FFS). That trio was a complete success in the end, be it at a very late time.
-Music: That one was pretty bad. Again it wasn't until late in the event (17th attempt) that I got one animal (Lullabison), but then it got worse: I got two more Lullabisons but I did not get the Tubacan until 2-3 days before the end of the trio. I only managed to put in 2-3 (largely sped with whatever few precious gems I had then) shots at the Melodeer, and quickly got a 17 hour timer. Yay? Well, "Nay!". It was an Aperil Fool playing a prank on me. That was a BAD fail. I never got the Melodeer, but I do have a Harmonic Hollow in which there are two Lullabisons and the one Tubacan. The other Lullabison is in a big earth plateau.
-Service dogs: So, here we arrive at "the trio which name shall not be mentioned": three straight weeks of breeding hell without getting ANY of the dogs. A complete waste of time hadn't I gotten some 2-3 fails that I needed still (Grassquatch + Rubble Rooster at least). I had early on decided to use a preciously freed space for the habitat. I sold that a few days before the end of the trio. No fun at all.
-Skull: in light of the very recent total Service disastrous results my hopes for the Skull trio were very low, and so it started out with fail after fail, but... then already on the 3rd day I got the SG! Finally a trio animal that was gotten early in the event! Next, when the SS was released, I got it on the 2nd attempt and couldn't believe my luck, and yes, for once lightning did strike twice or thrice, as I got the DW on the 2nd attempt too! In the past few weeks I've gotten 2 more SSes, and 4 more SGs (2 SSes and 1 SG were kept in a second Land of the Dead habitat).
When a trio plays out like the Skull one has for me, it is actually fun, but I really don't know what gives and why for this trio I'm getting such excellent results whereas the Service trio was completely 'barren' for me and didn't yield a single Service animal. Then, this time round again we see that not everyone has the same luck, as again some people are not getting any animal at all, whereas others get multiples. Go figure....
I hope you get the rest of the animals too. Should you not get anything until the day before the end of the trio and should you desire to keep the habitat, as a last resort you CAN fill it, by force-breeding two more SGs. Simply breed your current SG with a Pandaffodil and you should force-breed another SG. Not ideal, but at least you can fill the habitat then with those three animals and perhaps keep them in different stages of development...