Moved from Gall Wasps.
Something for the wingless adult insects page, if not the arthropod pathogenic fungi page.

Yes, it is a female brachypterous eupelmid with the mouthful of a name Eupelmus dryohizoxeni Ashmead, described way back in 1886. It is a relatively common parasitoid in cynipid galls, and its species name was based on the generic name of the cynipid making the gall from which the type series was reared. I am not exactly sure what you mean by the spikey thing sticking up unless you are referring to its shortened fore wings. They are naturally bent in an L-shape so that about the apical half sticks up vertically. This species is very similar in habitus to another species, Eupelmus vesicularis (Retzius), of which there are quite a few images in BugGuide, but your lateral images show well one of the major differentiating features. In E. vesicularis the mesoscutum and scutellum are flat, but in E. dryohizoxeni they are quite conspicuously convex so in the large image shown above the top of the thorax is somewhat M-like.

The cool "backflip" was first recorded in the North American literature back in 1869 when Walsh and Riley described another eupelmid, Anastatus mirabilis. Back then they wrote in a much more poetic way than the dull way we do now in the scientific literature and stated "And in this genus -- wonderful to relate -- the insect rolls itself in an upward instead of a downward direction, like a clown turning a backward sommerset...". Sometime later another author dubbed the species the "backrolling wonder", but this applies equally well to most females of the subfamily Eupelminae and about as close as a common name for the group as there is.

I hope that you measured it, or that you can estimate the size. It is helpful to add that info.
Nice find. I am always glad when I find both legitimate residents and parasitoids.

Images 726585 thru 726590 are of the emerged female eupelmid. The other adult images are of the gall wasp. I guess we'll have to wait and see on the larvae.

Regarding the dead one, eupelmids, in particular, often die with their head and abdomen bent up over the thorax.

Dr. Gibson discusses their unique jumping abilities quite a bit. See here for example.

But you probably should have submitted this series separately, cross referencing the others with thumbnails in the "Remarks" section.

They'll need to be unlinked and then relinked if, as seems likely, they're not Cynipids.