I got a question about syphilis's??

one of the woman at work were talking about something her grandfather told her.. black syphilis...he said the men got that during the vietnam war.. and they could not come back to the states because of it.. and that is why there are so many listed MIA.. she went on to tell me that they would clap wooden boards to gether on his member to get rid of the puss.. but there was no cure so they had to due this often..i have never heard of this.. but as she was telling me.. everyone around was all ears...is this true.. did this happen..?