The last couple weeks I've been getting + Missing Photographer contact info + rejections. Using the same release form as always, so this must be new. I can't find a place anywhere on the IS model release to supply that information. Am I blind or does the reviewer wrong in requesting this?

The only info for photographers on the MR is this:
Photographer/Filmmaker Information
Name (print) _________________________________________________
Signature ___________________________________________________
Date signed (DD/MM/YEAR) _______________________________________
Shoot Date __________________________________________________
Shoot Country & Region/State __________________________________
Shoot Description/Ref. _________________________________________

Nothing for photographer contact info

On my MR, for photographer info, I also have the full address, email and phone number. Check iStock's MR and correct yours to have the same info as them.

A MR is a contract between you and the model so it should have those infos anyway.

Just contact support. You are right and they will understand, I guess. No photographer info on Istock MR.

This is a MR that I'm using, and I never had any problems.