Hi!
If I read the post correctly, the guy said he didn't want them anymore and if the OP didn't take them, he would let the landlord deal with it. I would take that to mean that he pretty much gave them to her. She did leave a note for the landlord when she took the silky. If that is case, they are technically hers and the point is moot.
The only thing is that he said he paid for a neighbor to take care of them while he was gone, so if he doesn't want them, why did he pay someone to feed them? Unless he really didn't want to deal with getting rid of them until he got back home.
OP, I, personally, think it's great that you are looking out for them, but be careful. If he did tell you that you can have them, get it in writing. Do you know his address in India? Perhaps you can write him to make sure that he really is letting you have them.