When I frst got my dog she was 3-month-old, and I had to crate all day 'cuz like you i work too. And even when I am home I had to crate her sometimes too 'cuz i had to cook. Oh yes, she cried and whined a lot......the only thing you can do is: TOUGH IT OUT....what I did is to ignore her, and very important is: ask your family do the same.....And now she is 6 month old and she rarely whines in her crate. She will for a bit but will quiet down after one minute or two. Puppies are just like kids, if you give them attention when they whine they will do it more next time....I tried the shake soda can too, and as you said, sometimes it works and sometimes it doesn't.
Anyways, crying is just a phase for puppies, they will grow out of if. Just be strong when they cry......Good luck.