I found a pretty good article on his options as an UDFA now http://overthecap.com/what-can-lael-collins-earn-as-an-undrafted-free-agent/. While he will sacrifice the bonus that a drafted player gets, he gains a lot of flexibility in being able to chose a team, renegotiating his contract, and what year he hits free agency. Also he can get his entire salary guaranteed if i'm reading correctly and he won't be making that much less than a player drafted on day 3. All in all I think his agents made the best decision they could in the limited amount of time they had.