Kelly,
I love your books and you usually have excellent advice.
But this is directly from the LoewsFirst website under terms and conditions:
2. LoewsFirst benefits and mileage or points awards are based upon completion of a qualifying stay at any Loews Hotel. A qualifying stay is any rate published by the hotel. Group, negotiated, third party, government, Universal Passholder and Universal Florida residents rates do not qualify. Not valid with any other discount program, coupon, complimentary or promotional offer.
LoewsFirst has told me on numerous times that any stay booked by a third party, with the exception of AAA, will not accrue points. You may still get your benefits at the hotel, such as the welcome gift, but your stay will not accrue points towards the next level.