As I understand it, while the Germans OTL were also on the wrong technical track, the real barrier to their having an A-bomb by 1944 would have been logistical. They had access to uranium in whatever quantities they'd have needed, but the US Manhattan Project was a huge investment of resources. At one point, so I've read, they were authorized to take all the silver out of Fort Knox to fashion it into wires for cyclotrons. (I think they actually didn't do this as it proved unnecessary, but it shows how all-out serious the government was about pursuing any means necessary to achieve the goal, and the sort of economic scale they considered).
The USA had access, during the war, to most of the resources of the world. We had an economy that, with full employment, was the largest in the world. Even so it took most of the war to work our way to Trinity, at the end we'd fashioned just three bombs--the Trinity test shot, Fat Man, Little Boy. That was it. A few years later during the debate about whether or not to perform the Bikini tests, one reason Leslie Groves was against them was that three bombs were a significant--it was classified, even from President Truman, just how significant--fraction of the total American stockpile. And that was postwar, when the USA was no longer making an all-out war effort on every front, but the bombs were one of the few top priorities left and they were fully funded.
In order to make those three bombs, the Project had facilities and people mobilized all over the country, at major universities, at at least three major sites (Oak Ridge, Hanford, and of course Alamogordo). The New Mexico site was where the science and design engineering took place, but the Tennessee and Washington sites were where the materials were processed.
It was processing ordinary uranium into sufficiently concentrated U-235 or plutonium that was the killer. No amount of ASB foresight could make this task much easier; it could save effort in developing alternate lines of approach but in the end even with a perfect right guess as to the most cost-effective approach, the process of taking raw uranium ore and converting it into weapons-grade materials was a slow, expensive one.
For Germans to match that effort, they'd have had to devote that same scale of resources, and develop processing sites that were secure and that would remain secure in the face of Allied bombing and seizure of territory. OTL, the major German secret projects usually had to relocate at least once, sometimes more often than that, as Allies either bombed their sites or as the Russian armies advanced on them. It was bad enough having to relocate von Braun and company from Peenemunde to their redoubt in the Alpine foothills, but there is just no way they could simply move the whole elaborate massive setup necessary to concentrate weapons-grade fissionable materials. The only way they could keep them going would be if they presciently foresaw their own near-defeat and set the facilities up in locations both totally undisclosed and invisible to Allied high-altitude scouting, fortified against bombing should the Allies somehow learn of them anyway, and located in the central Reich where they'd be the last regions overrun by Russians or Anglo-Americans. Such foresight would be deemed defeatist of course, and the efforts to hide and fortify the sites would greatly add to the already astronomical costs.
But even if the German technical community were not disrupted by Nazi ideology, they'd need these rather ASB breaks--of intuitive focus on the most cost-effective approaches, of "defeatist" ultra-pessimistic insistence on maximum fortification and secrecy of the extraction sites--to stand a chance, even if their science were superior to Allied rather than retarded. And the cost would be draining on all other extreme technical ventures and indeed on routine logistics, a drain that goes on for years before it can even offer the promise of a payoff. Which when it comes amounts to a literal handful of bombs.
Then and only then do they face the question of how to deliver them.
V-weapons of course include the V-1 as well as V-2. It's not possible and not necessary to try to launch a 4 ton bomb on a rocket, true. An ordinary V-1 pilotless airplane can't lift one either, but I'd think that as the bomb design took shape and the materials were accumulating up toward critical mass, it wouldn't be so difficult to design a scaled-up V-1 type drone airplane that could do the job. Especially if the goal is merely to strike at a Soviet frontal concentration, then the drone bomb-plane would be flying mostly over German-controlled airspace.
If they want to take out Leningrad or Moscow instead, that would be pretty tough to do, I agree.
But I don't think the Reich was up to having even one bomb ready by 1944, even if they didn't drive out a lot of their best people first. It's just not realistic that they should avoid all the dead ends, wasted effort, etc that the Americans had to make as part of the trial-and-error process of learning what would and would not work. There was no cheap and easy way to get weapons-grade fissionables available even with the most brilliant strokes of luck. The A-bomb was a typical product of American advantages in the war, which were mainly based on the sheer mass of economic resources available to the Allied side.