Upload & Sell: Off
From your first post to your next you sound more hopeful than expectant. In my experience those wanting work done for text books and 'other' publications either can get what they want for pennies from stock, or they want yours 'for the exposure' it will give you, a link or your name somewhere nobody will ever see it. Only amateurs give their work away, in hope ...
I suspect every good macro photographer has been propositioned with the promise of paid work after a 'trial' period of working for links. It's an old con. Doesn't mean it couldn't work for someone with 'connections', but without them I wouldn't be counting chickens, I'd be asking for money.
If you are any good, and we haven't seen any of your work, I wouldn't bother with 'promises'. Bottom line is if 'they' don't want to pay you something they don't value your work - a bad place to start a business relationship.
And you can bet your bottom dollar 'they' are getting paid. No?
PS If you want to get into forensic photography why not approach the police, or whoever does it where you are.