It may not be exact answer, but you can use both. 昨日の夜のことは覚えていない 昨日の夜のことを覚えていない However, I feel "昨日の夜のこと" is emphasized in the first sentence rather than the second one.

The difference is clearly appear in conversation. =Conversation A= "What did you do last night, Ron?" ロン、昨日の夜は何をしていたの？ "I don't remember about last night at all" 昨日の夜のことは全然覚えていない。 =Conversation B= "What's the matter with you, Ron? You look worried" どうしたの？ロン。心配そうに見えるけど。 "I don't remember about last night at all" 僕は昨日の夜のことを全然覚えていない" ...You cannot use を in A , and cannot use は in B. The difference between them is the topic of conversations. The topic of the conversation A is "What Ron did in last night". The topic of conversation B is "The reason why Ron looks worried". は is the "topic maker". Japanese sentences are composed by "topic and comment". For example: 私は走る(I run) 私=topic/ 走る=comment. It's similar to "subject and predicate", but they are different a little. Because 私は走る and 私が走る are different sentences in Japanese. (私 is also the subject of 私が走る. But it's not the topic). We use は to make a particular noun as the topic of sentence, instead of が/の/に/を. So if the conversation B goes like below, you cannot say "その理由を". Because the topic of this conversation is "The reason why Ron looks worried". "What's the matter with you, Ron? You look worried" どうしたの？ロン。心配そうに見えるけど。 "I don't want to say the reason why". その理由は、言いたくない。