You didn't chip/wear down a rod guide insert by having a too tight drag using braid, no matter which brand you use. You dropped/hit it on a hard surface to crack it. Or you may have reeled a lure line tie into the insert and cracked it.
Walmart carries rod tip replacement tips in sets of three, with one that may fit your rod. If the guide set doesn't include the hot melt glue, get some of that too.