The biggest mistake I see people making trying to get their horses barefoot, is starting by taking shoes off. That’s not where you start.
You start with getting a healthy foot IN the shoes first, when at all possible. Of course there are some situations where you can do both - take shoes off the crappy foot and still keep him comfortable when the footing and diet, and judicious use of boots, allow that to happen.
What you don’t do (and I don’t mean this to sound harsh, but it might come across that way) is take a horse who has a history of laminitis, doing well/better while barefoot on a dry lot with hay, and throw him out on to 40 acres of pasture.
I don’t know how in the world your farrier has determined that his feet aren’t sore due to laminitis, especially in the face of him also saying “he’s growing good sole”. What does he say the soreness IS related to? 
I agree that we really need good pictures to offer more helpful advice from that perspective.
But from the management perspective, I think it’s a must that you assume his soreness is 100% laminitis, get him off that grass until he’s no longer sore, and then re-think how much grass time he is able to have. Maybe none, maybe all day with a muzzle, maybe less with a muzzle, maybe a few hours a day without a muzzle.
Putting shoes on now is not giving up on barefoot. Way, way too many people get too attached to keeping shoes off, that they aren’t focused (enough) on what it takes to get the horse the most comfortable, the fastest. Often, the fastest way to a comfortable barefoot life IS to work through the issues with shoes on, and then transition at a time of year when the ground is more conducive to allowing the foot to adapt.
Read through this link to see how to take pictures good enough for critiquing feet
Good Hoof Photos - How to take Good Hoof Photos