Chicken – cook the tandoori chicken in the marinade for a sauce

Soy sauce is pretty salty. It sounds like a great deal of water diffused out of your chicken and into the marinade, which significantly changed the texture of the meat.

It's not uncommon to do something like this on purpose. When you make gravlax, for example, you cover a piece of salmon with quite a bit of salt and refrigerate it for a day or two. The salt draws out a lot of moisture, causing the fish to firm up considerably. Even though your soy sauce marinade was liquid, it still had a much higher salt concentration (or to think of it another way, a much lower water concentration) than the chicken, and would have had the same effect.

I have been in this situation before and I did try freezing it. When I used it later on, it did taste and feel OK, but as you would expect, not the real fresh taste.

I do not think the ingredients in the marinade will have any effect while it is frozen. While thawing, the yogurt might split, leaving more than usual water, but that shouldnt alter much of the outcome. It will be still good after defrosting; I would normally defrost by leaving the item in the refrigerator overnight, rather than quick methods like microwaving or even leaving at room temperature on the kitchen counter.