I would assume Alford, Warmoth and Greene is not enough to get Yelich as they posted on MLB.com.
I do not see why Pillar and Travis could not be used as chips. Yelich replaces Pillar, and the Jays then are not forced to go after some huge name in FA to help out the OF. They could be good with a cost-effective guy like Dyson, rather than splurging on a Cain. I think the Jays would be willing to give up Travis given he would help get a big piece in return, they do have immediate replacements in Diaz and Solarte, both with some good amount of control left, and they still have ample depth now and in the future at those positions. I am sure they would love to keep Travis and see him become a productive 2B who stays healthy, but that is unlikely to happen and even if it did, I doubt they would think super long about using him to get someone of Yelich's quality. Throw in some good prospects, and I think you could have a deal that works.
Yelich clearly has a ton of value, but all of the deals proposed typically involved pure prospects. What is wrong with trying to instead give up some MLBers with 3 years of control left each, do not make them take on more salary (I believe they'll actually cut salary, not that it would be the motivation of a Yelich deal) and can help Miami put a decent team together now and in the future, which regardless of how much money they need to shed, they still need to do. Fans are pissed they are selling off guys all over the place and what has Miami even done to replace any of that quality yet? Getting controlled pieces that can help now should be something they look for, and Pillar and Travis do that. Pillar takes the CF spot, Travis takes the 2B spot where Gordon was, and at least you get something started for less than what Yelich cost.
Castro (if they keep him) and Travis gives a decent SS/2B duo, as long as they have some insurance for Travis.
EDIT: Turns out, even if they traded Castro, they'd still have a decent infield and some depth as well.