This is the Second time that TMF has deleted my message for taking too long to type it, so hopefully I can write this one in peace!
Sorry for such a late reply, this has been a mini rabbit hole for me & like I said TMF doesn't really seem to enjoy all of my typing
Anyways, yeah, the RCA Victor marking on the label has been about the only thing I could find on this label, but I've photographed all of the different "types" of markings on both labels, & I think I've found some good things, so please forgive my ramblings!
First, the Paprikás label.
This label has 3 types, or being more specific, 1 type with two variations, & one anomaly. The first type is just a W, followed by a number, & then an A/B. Neither the number nor the A/B correspond to the matrix/side information listed on the label. I put two different pictures because the variation I mentioned earlier is in the run-out groove style. The first two pictures are of the same record, & both sides have a different run-out groove, & before you ask, the A/B doesn't correlate to that either. The Anomaly is the third image, featuring no W, & a longer number that still isn't the matrix number on the label. I can't tell if the A marking is also an A/B because this record is the only anomaly & it has A on both sides. It also has the same runout groove style on both sides. While the first style of run-out groove does seem to look similar to Decca, the two types of run-out groove on one record reminds me of a 40s Parlophone record I picked up at a show recently. It has a different style on both sides, & they seem to be the same style. The stamped font isn't the same, but it also doesn't seem to be a Decca font either. Maybe they are Parlophone masters that had their Matrix numbers taken off & replaced with new ones.
Now for the Czárdás label. This one is a bit more complex, so ill go through the 3 different variants separately, starting with the RCA Victor version.
This one has a feature present on all of the records, a stamped version of the matrix info on the label. This one is the only one to feature a stamped A(that almost seems to be scratched off a bit... it looks more like an A in person than on the picture), the A stamp is on both sides.
This one also has a stamped "1R" on both sides.
Now the second RCA Victor record.
Has the same stamped matrix info (although without the A mark), but also has a second number thats different on both sides (The B-side even features the A mark, but in a different spot!). Speaking of side B, the end of the number does have 1R at the end of it, maybe that relates to the 1R on the other two?
Now the Decca(?) Style pressing.
The information on the first RCA Victor record is basically the same on this one. Features a stamped version of the matrix info (again without the A mark), & the "1R". The only difference is this number. It has the same number but increased by one on the B-side.
These all seem to add up to them all being pressed by RCA Victor, slightly differing info but I doubt that conformity would be their(RCA Victor's) number one concern (considering the differing label types, these could have also been made at different times, when RCA Victor would be using different ways of marking records.). There is an anomaly in this label type though.
This label features a "C-501" stamp (Which both increases to 502 on the B-side & is not the label listed matrix number), and a very faint but definitely visible backwards S marking (too faint to capture). I'm wondering if this is them going to a different company, I did just mention RCA Victor probably not caring much about conformity, but this seems very far off. Different font, different run-out groove style, & different markings. Probably most likely solution is that this one is a master from a different company, but I don't know enough to identify that.
Forgive me for this huge rant, but like i said, this has been a mini rabbit hole for me the past couple of days! I hope this information is helpful.