In my opinion, the rooms at the HDR are more or less Motel 6 quality, unless you get one of the more expensive suites. The basic rooms are prison cells without windows in many cases. Also, the HDR charges a $10.00 per chica per ride up the elevator...this "guest fee" can add up very quickly. Yes, the Hotel del Rey is prostitution "ground zero," the action (with high- and low-tides) is 24/7. Bar prices are at U.S. levels (high for SJ).
The Presidente is trying, it seems to reduce/eliminate whoremonger business. They have a fairly strict dress code for hookers...no bare bellies, no short-shorts, no cleavage. A nun's habit works.

Guests are limited to one girl per visit...kiss the idea of threesomes goodbye if you stay at the Pres. Luxury hotel for SJ, especially if you get one of the spa suites. Good restaurant/bar on premises (expensive). Casino (no working girls) on premises.
Have you thought of the Hotel la Amistad? They are a CRT V.I.P. sponsor (you'll get a good discount if you are a V.I.P. member of this website). The rooms were all recently renovated, as was the lobby area. Excellent breakfast included in room price, very close (1.5 blocks) to the Sportsmen's Lodge, a block from a pharmacy and two from a hospital, 5 quick blocks to New Fantasy massage.... and the staff and owner are great! I divide my visits between the SL and Amistad, although I like the Castillo as well; the Castillo doesn't offer quite as many amenities, but they do give substantial discounts for CRT V.I.P.s and especially if you pay cash.
On such short notice, I'd try to book into the Amistad. If they're full, consider the Castillo if you can lower your need for luxury a bit.
HTH. Be sure to read the Hotels section for more ideas and for other CRT V.I.P. sponsors, like the Hotel Freebird, Clarion Amon Plaza, Vesuvio, Dunn Inn, Hotel Little Havana.... Hey, now there's an idea. I wonder if you could get one of the suites on such short notice. Guests in the suites (not the regular rooms) can hire masseuses/personal care consultants for $25.00/hour!
Wherever you stay, be sure to introduce yourself around the SL bar during Happy Hour. You'll find lots of CRT brothers to swap stories, get information or to wing with you. Have fun!