Yeah, most of my cleft graft failures for citrus were from my incorrect assumption that all citrus are graft compatible with each other. And last year all my Prague grafts callused but none of them ever grew. Two of those are still green stems with no growth more than 18 months later. My Prague cleft grafts from a couple months ago had 3 of 4 take and have grown well, though.
I put 3 cleft grafts of pink variegated lemon on my meyer, a 3 took but only one has pushed any growth yet. But it’s due to the other two being low and the one growing is high so that’s an apical dominance thing I assume. If they don’t grow I’ll take buds off of them and try some chips next spring