Well I have managed to perform the challenges, although the ruling continues, I did the following, played on the highest difficulty (I don't think this has anything to do with it), I did it so that there are fewer people, and I made the route of the cave of the Tarsis base, when leaving that point on the left, if you go down you will find a creek and a cave that passes to the other side of the base, in that cave there must be one or two arcanist collectibles, take them over and over Once, I've counted more than 15, and after that, the 15th, 16th or 17th time I grabbed it, I started counting, after that all normal, every time I grabbed it I counted for the challenge, then I went for the sentries and it worked correctly, I only had to grab 25, in case of not working with the sentry ones they could do the same, in case of finding it elsewhere, they just have to go away in any direction (I did it until the suit overheated) , and return to the same place and the collectible will appear again, this will also It served two more people to get the challenges, I hope it serves them, good luck.
