I must confess that I didnt read each and any point in the current discussion, but I come to the conclusion that you try to build up an immense rulework to cure a limited problem.
I don´t like the basic idea behind it, as you try to limit the things users can do in an extremely strict and complicated framework.
I´d like to suggest something different:
Seperate the "Buyer" and the "Seller" side of the transfers.
Read:
If you sell a player, it´s -always- selling it to the "Big Buzzerbeater Union", which pays a set price. The price is always shown on the player page and is calculated in a way taking salary, skill sum, age, potential, maybe role or achievements and intangibles into account. The prize is independent of any bidding, but cannot exceed the buying price within the first 5 weeks after purchase (slowly "gaining ground", starting at 75% of the starting price, reaching the purchase price after 5 weeks and then going by the formula), and is not payed by any one user but by the Buzzerbeater Bank. The sale happens immediately, without any delay.
Sold players are getting FAed, and enter the FA market. He will be up in the list up to three times before retiring, first time at a starting price of 10x his salary, if nobody wants him 7x, if still nobody tries to get him, final effort at 4.5x, then he´s gone. Usual 3 days of auction time, money goes to the Buzzerbeater Bank.
No connection between buyer and seller - players actively "trading" have to go for steals while buying, but cannot rip apart anyone but the Buzzerbeater Bank.
You immediately crush 90% of the cheating possibilities, active players will be rewarded for their finds, still there´s no victim.
Zwei Dinge sind unendlich, die Dummheit und das All...