[RadioKid]

>お兄さんが嫌いじゃなさそうな景色でした。

It seems to be correct but not natural.

I would say "お兄さんが嫌わなさそうな景色でした。" or rather say nothing.

>お兄さんが嫌いじゃなかったさそうな景色です。

It has some grammatical problems. And I cannot imagine the situation. the brother have never seen the scenery, right? Then he never hated the scenery.

I would say "お兄さんが嫌わなさそうな景色だったよ。".