I would not book through an intermediary unless I save a considerable amount of money (say, 20%). You don't say which hotel you'll be staying at or what the room rates are, so it's hard to say how much (in percentage terms) the $7 amounts to. Also, booking through a third party often means paying in advance; sometimes the rates are nonrefundable; and you can't take advantage of lower rates if prices later drop.

In practical terms, I have found hotels.com to be cheaper for my stays only when they offer discount codes, but when I use those, hotels.com denies me credit in their rewards program, making their rewards program useless for me.

There are many ways to get Hilton Gold status (such as getting one of their credit cards) without having any stays credited, so you could also pursue status in other ways.

Finally, be sure to check all the Hilton discount codes that you qualify for. Between the AAA, corporate, and MVP rates, I rarely need to go anywhere other than the Hilton Web site to secure the best rates, and I am guaranteed to get points and the benefits of status.