A couple of things here...(someone may have already provided answers but I didn't have time to read through the entire thread).
First, just because Coach A spent $27,000 on a recruit and Coach B spent $12,000 on a recruit...does not mean that Coach A should sign said player. This is for several reasons but I'll just address the three main reasons. 1. Depending on distance, that amount could have a significantly different value. 2. It's not how much money you invest in a player, it's how you invest it. There are a number of different tools, all cost different amounts and all have different effects on recruits. 3. Recent success can give one coach an advantage of another coach. I know the difference in amounts are significant but understand that it isn't just how much you spend on a player.
Secondly. I don't believe that two coaches piecing a deal together is definitively collusion. It's more of a gray area, unless it involves two coaches specifically targeting one coach or one conference. However, if it's two coaches in the same conference, that just don't want to battle over an average offensive lineman...I don't see any issue with one coach sitemailing the other a, "how much do you really need him?" message. If two coaches are discussing the scouting report of player, if the amount spent is disclosed before the recruit signs, or if one coach jumps on a recruit with the intent of not signing him so that his buddy can sign him, that's different. Those are clear violations of the fair play guidelines.