It turns out that inside your
weights2 dataset, you have another
weights2 folder which contains the file you need. Here's the fix:
floyd run --gpu --data /datasets/train/1:/train --data /datasets/test/1:/test --data /datasets/weights2/1:/weights2 "make && ./darknet detector train cfg/obj.data cfg/yolo-obj.cfg /weights2/weights2/darknet53.conv.74"
Hope it helps.