From what i’ve read, Johan relies on trauma, and neither member of the duo has any that they actually care about anymore, and Johan also has no way of knowing exactly what it is.
Clover also has
Mind Reading, which, while vague, in general would let him know if Johan or anyone he sends is trying to manipulate him via persuasion, like looking through his memories and seeing the stuff he plans or reading what he is currently thinking about. And at that point it’d become useless entirely to SI him, so I have no reason to believe Johan could do this to him in particular.
Also, how would Johan even SI them without getting close? If he is anywhere nearby the duo then he is dead the moment they see him. I know he can send people but they would not have nearly as much convincing power as Johan does, and if the duo knows they are with Johan they’d die before they could get more than a sentence out.
Logically they do if clover knows what’s going to happen in the future like he has precog. That’s why fights get easier for him each time
he comes back. Subaru from re:zero for example uses a very similair ability to fix all the mistakes he makes, and the duo would be able to do the same thing and make it way harder for Johan to outsmart them.
SI is very unlikely to work against the duo for the millionth time especially with clover being to mind-read, and pretty much everyone here agrees with me…