Very Sorry, he is lucky to have you to help him through this. I agree with the above post, if you share what he has tried it can help others add or give some advice about what has worked for them.
I have microclots and started on
-NAC with Nattokinase (away from food am and pm) (Nac is 600 mg)
-b vitamin complex (I need a methylated form so if you dont know Id get that to be safe)
-Ketotifin (antihistmine) 1mg I take before bed because it makes me drousy
-baby aspirin
-Quercetin and bromelain tablet once a day
-electrolytes (I like the cure brand bc they dont have all the added ingredients
-I have also just heard that pine needle tea or dandelion leaf and root tea is good
I also agree about a good healthy diet without preservatives, low gluten, ect... just eat as healthy as possible
other things that can help are intermittent fasting, ending a shower with cold water, box breathing and getting out in nature to ground (in the ocean if you are close) or in the forest to sit next to a tree.
Its not easy but so many are working through it and finding answers, keep the faith. Sending my best