yeah fiber owner does the repairs, but they can charge the offending cutter the full cost of repairs, and possibly any credits that where issued to customers (mostly those with SLA's). IF the company in question did a "call before you dig" then no, i dont think they should be outed unless they blatantly ignored the flags, but if mediacom didnt mark the line or if fiber owner didnt mark the line, then its on them. if however the company didnt bother with "call before you dig" i would definitely do the name and shame game, pointing out why its important to make that simple phone call.
no reason not to. ive done it for something as simple as putting in a mail box, of course we have an ATT fiber line out back, and out front. in fact when a wreck happend here i think 2 years ago it took out that fiber out front. internet for the entire sout east was affected (including mediacom) and we get those lovely "highly explosive pipeline thats not marked until you call" notices twice a year.