Has the existence of earth-sized rogue planets been confirmed? The list of known rogue planets provided by Wikipedia is fairly short. Some are "candidates"; others "may be" red dwarfs. The two confirmed rogue planets are several times the size of Jupiter.

I understand that rogue planets can only be detected if they glow (which immediately brings the phrase "red dwarf" to mind) or if they cross the path of light emanating from a star. This makes detection extremely difficult.

The reason I ask is I'm not quite certain whether objects the size of Jupiter or smaller can even exist in interstellar space. Maybe dark matter grinds them to dust, or maybe they implode in the absence of any meaningful inertial frame - I don't know. Has anything Earth-sized been detected out there?
The list on Wikipedia looks current. It doesn't list planets that have only been detected as one-off microlensing events. This can detect Jupiter sized objects (with considerable uncertainty in mass). But observing a microlensing doesn't allow for study, so a microlensing is not considered to be enough evidence for naming or cataloging a known planet. So the short answer is no Earth sized rogue planets are known.

This is entirely due to the difficulty in detection. An Earth sized rogue planet would cool on its surface to a few degrees above absolute zero, and be undetectable with current telescopes. Microlensing events with small rogue planets would also be smaller and harder to detect above noise. 

An Earth sized rogue planet has a perfectly good inertial frame, (it is the bound planets that are in a rotating, non-inertial frame), nor does a frame of reference have anything to do with implosions. Dark matter is doesn't grind anything since the main property of Dark matter is that it doesn't interact with regular matter.

In all likelihood, there are billions of rogue planets in the galaxy, and some are smaller, and some are Earth-sized and "rocky". They could have been formed around a star and then ejected.