I still say , listen to the structural engineer , this is his baby....I wouldnt ask my fellow architects about building an engine...I`d listen to an engine builder for that...if the engineer is California refgistered (which he obviously is if he works there), he`s taken test on the quake structures as part of his registration ,and VERY PROBABLY done a few structures before...not just a few.....

if he says blocks will work ,they do...they will work like a conc wall since they are reinforced,..and if any cracking occurs , it will be cracking along the joints (not always), rather than irregular cracking...its not the concrete that holds the wall up, its the reinforcing...

just like freeways and house slabs around Houston ,where we have very expansive (and then shrinking) soil, no concrete holds up to that, maybe 25 yrs,but after "bending" back and forth for 20-30 yrs it cracks....but the reinforcing holds it together...

my std comment to home owners here is : there are two kinds of concrete slabs , the ones that are cracked and the ones that will crack!