Question

I ______ gotten to the hotel two hours ago, but my flight was delayed.

Answer 1

I would have gotten to the hotel two hours ago, but my flight was delayed.

There is no scope of lengthening this answer, as it is a fill up.

Hope it helps.

Answer 2

"Gotten" in American English is used properly when referring to  the past participle especially in a process of obtaining something. 

"Had gotten" is the correct form in American English when referring to past participle. 

Therefore the correct answer is;

I had gotten to the hotel two hours ago, but my flight was delayed.