>He's wearing easyboot Rx,

You can undo the velcro. 

Depending on how snug they are ,he will either step out of them - in time- or you can hold on to the heel part as he steps.

I would do this on sheets or large towels,or something other than stable mats,or ground.

If he steps on a towel (large hand towel?)that will cover his foot ,you can bring the towel up his fetlock/leg and secure it,so that the foot is kept clean,or can lose some of the pus on the towel, or.....provide a breather for you both.

>also tried the rescue remedy seems to help but not enough to get his feet done, 

Maybe try more.