Is Eden real in Logan?

TL:DR ; 'Eden' as depicted in the comic book is not real, but is a representation of a real prospect for sanctuary.

Gabriela never claims that the co-ordinates will lead the children to 'Eden', at least not in the form it is depicted in the comic book. It is only after Logan see's the co-ordinates in the comic book that he makes the assumption that this is why Gabriela is trying to get Laura there: out of some idealist mythology based on fictional propaganda intended to be “ice cream for bedwetters”. Just like Dr. Rice, who assumed the hospital support staff were "too poor and stupid" to understand what was happening, Logan has underestimated Gabriella's intelligence.

After reading the comic book, Logan believe's Gabriella brought Laura to him because she thought Eden was literally existent and The Wolverine was 'a real hero', a perceived naivety which Logan is at first angered by.

The real reason Gabriela does this, however is because her unseen and unnamed contacts who are arranging sanctuary for the children have set up a rendezvous point at the co-ordinates. This is no accident, or co-incidence; using a location in a 'comic book' is a clever cypher that would evade detection. If each child were given a comic book that contains those co-ordinates, even if they were caught in possession of it; it's just a comic book. Infact, the only reason the location is identified in the first place is because the transigen-proxy mercenary Pierce finds the co-ordinates written in plain sight, not 'hidden' in the comic book. Not only will the comic book 'hide' the location of the rendezvous, but it's likely the younger, more naive children really did believe they were heading to 'a paradise': a necessary deception to help motivate them in their journey, and allay their fears.

When they arrive at 'Eden', the older escapee Rictor explains that this was always the plan: to embed the idea in the children that they had to arrive in this destination by a certain time, in order to move safely across the border on schedule. The fact that Riktor is seen communicating via Hamm Radio to an unseen person, and confirming safe passage is enough to confirm that these contacts are very real; and the fact that Dr. Rice instructs the mercenaries that they must prioritize intercepting the mutants before they cross the border confirms that there is some kind of sanctuary for them, and it is a very real impediment to their re-capture.

Additionally, Gabriela brings Laura to Logan not because she thinks he is a knight in shining armour (as Logan assumes from reading the comics), but because:

Laura is Logan's Genetic 'Child', and her best choice of ward is someone who feels a connection or a sense of responsibility towards her (which, whilst seemingly a mistake at first given logans disposition, proves to be well founded)

Well, we can't really say that it's not real. But that comic book is specifically designed for the movie only.

From The Wrap

A young girl named Laura, on the lam from the scientists that imbued her with mutant powers, shows the book to Logan; he scoffs at it, suggesting that the comics are filled with lies and exaggerations. But, as Audouy indicates, Logan is wrong about Eden being a mere fantasy — even if it doesn’t quite aesthetically match up to what’s shown in the book. Instead, it’s more low-rent Neverland than biblical paradise.

That comic was created specifically for the movie, in fact — it’s not a real-world “X-Men” book. As Inverse reports, the filmmakers decided late in production to make the comics Laura has with her themselves. They worked hard to mimic the style of real “X-Men” comic books, but the ones made for the movie exist only in Logan.

As production designer François Audouy told Inverse in an interview

That was something that happened very late in the writing process.

Jim had this wonderful idea of creating sort of a meta crossover where the comic books actually exist in the world of Wolverine, which I thought was really wonderful. It gave us an opportunity to actually put a nod to the comic books into the film.

The X Men cómics seen in the movie are described as being dramatized, fictional retelling of events that happened an unknown amount of time before the film. Logan says it never happened like shown in the comics and we have no reason to disbelieve him. It may have had a different name and location or Xavier or Logan would have recognize it.

Eden as depicted did not exist. But the coordinates made for a convenient meet up location.

From what I understood, the coordenates on the comic book point to the watchpoint, which was a meeting place and not the definitive "Eden", and the children built the refugee on that location inspired by the books. You could argue that Eden might exist across the border, but I think it would not make sense to portrait it in one location for it to exist in another.