I know when she is with him, for at least a minute of that time, she is thinking about me and what i'm doing. i need to amplify that
No you don't. You need to keep doing what your doing is all. If amplify means in any way pushing your marriage on your wife right now its a bad idea, she isn't likely ready for that in my opinion. That is way too quick a turnaround for it to be genuine.
Just keep doing what you are doing, she's showing positive behaviour. Keep up what you are doing, which is NOT pressuring her.
What did she say when you invited her to the gym? Did she say anything?
In the future when you do an experiment monitor and note her verbal response AND her body language and tone. Report back here.
My guess is she' didn't take to it or you would have said something.
The gym pass is much like the business card, but I think its too much since she knows you go there. If it were just for a girls gym as a gift then it still might be too much.
Just focus on your son and be a good father, most women find that very attractive and it does NOT pressure her..its a win win. You get to please and attract your wife while NOT pressuring her.