A DESCRIPTION OF THE PROBLEM :
In method ClassRemapperImpl.asCodeTransform() the bootstrap method handle needs to be remapped as well; see fix below:

case InvokeDynamicInstruction idi ->
                    cob.invokeDynamicInstruction(DynamicCallSiteDesc.of(
// idi.bootstrapMethod(), idi.name().stringValue(),
                            mapDirectMethodHandle(idi.bootstrapMethod()), idi.name().stringValue(),
                            mapMethodDesc(idi.typeSymbol()),
                            idi.bootstrapArgs().stream().map(this::mapConstantValue).toArray(ConstantDesc[]::new)));