Regarding Iskander missiles with improved terminal guidance.
The 9K720 Iskander-M uses the 9M723 ballistic missile, which is generally understood to use inertial navigation with satellite navigation updates and, in some variants, terminal guidance.
The following seekers are already in use on some missiles and it is not clear whether the Ukr report is about them or identified new or improved versions.
9E436 -. Looking for an optical adapter.
Produced by TsNIIAG, with NII Television also involved. Uses field or optical target images to support terminal corrections.
9B918 -. Looking for an active radar.
Produced by NPP Radar MMS. Uses radar measurements for terminal guidance, may operate when satellite navigation signals are disturbed.