Well, Rotel certainly makes quality equipment, is there a reason you’re thinking of switching?
As for the speaker cable being shorted, that can be done by visual inspection. Check at the connection points on the amp & speakers to see if the + & - wires are touching. In a severe case, the may be some scorching nearby. You would be wise to check out the speakers on another amp/receiver to make sure they didn’t get damaged in the incident.
As for a new amp, I’m a big proponent for used gear. My pre/pro, amp & even inter-connect cables were all bought second hand, and all sound great. Craiglist & Ebay are good places to check out. As for brands, B&K, Bryston, Arcam, Anthem , Parasound (as well as others) all make good quality items, and solid state equipment generally (despite your situation) lasts a long time.
Good luck