Again , I'm not there seeing everything. But a post will work against the wall instead of a 2-3 foot wall.
The steel plate idea is ridiculous, it will not work in my opinion. You already have wind issues, you don't need other ones.
Get your own engineer. make some calls and see who makes you feel comfortable, and comes up with your solution. There are so many different things that can be done ,you do not need a wall. There are brackets which can be fabricated, which would be as much as installing a wall and finishing it.
The crawl space is not an issue unless you have no acess. You can always install a pier to hold this beam wherever you want. You could install an 8x8 or bigger post where your temporary one is, it would look massive and be a conversation piece and still make it look good.