If I did like you, selling a ST who dont socre a goal, then I would have miss an excellent ST ...my current main ST was a scout when I bought him last season and he did not score single goal till 3 matches but after that he was beast with 51 goals and 22 assists ... so its all depends on how you take it
thats a good idea ... I will do the same ...train them hard and try in one more match , if they do well keep them otherwise sell them