Utila Water Sports is closed and doesn't look like it will be reopening. Carnival is a busy time and there will be some celebrations happening at some point in most dive centers. This will most likely take the form of a BBQ or similar.
What I would suggest is staying outside of dive center so you can get away from what is mostly a younger crowd whenever you want to.
It's fairly easy to choose a reputable dive center - first of all look for pricing, I know this isn't the be all and end all of it but in diving just like most things in life you get what you pay for. A dive center can't afford to keep good staff if they can't pay them properly. Quality boats and dive equipment can't be maintained without money. I could go on, but you get the idea. The instructor you get will be paramount to your satisfaction during the training. My guess is you don't want a young brand new instructor who wants to party during carnival so ask about this when you make your inquiries.
If you want professional instructors in a professional dive center that puts you first rather than their party, then look for a dive center that charges enough to pay professional experienced instructors enough to stay and work for them for an extended period. Look for a dive center that has multiple boats and if you are really worried then request your own instructor for a small two person private course.
Prices are not the same on Utila anymore (those days are long gone). You'll find prices varying from around $220 to $299. Make sure everything is included, no hidden costs. Ask about staff experience, staff training, in house training, boat quality and equipment. You are meant to be getting an Open Water Manual and dive table to keep as part of the course. Make sure you will receive your own new copy to take home with you.