What is happening here is that your recipient's spam filter is affecting the links and popping the "suspicious" redirect link code from our tracking up into the content itself. The way to test this is to send a copy of the campaign to this recipient with the tracking turned off and see if that displays better for them. If they have an IT group, only they would be able to say why this is happening, and if not they may want to look at their anti-virus software to see if it's killing the link code and bringing it forward.