The coaches are only banned from INITIATING contact. That includes call backs, responding to an email or text, etc. If the gymnast initiates it and is able to speak with the coach right away - calls the coach and he/she picks up, visits the college and the coach 'happens' to be there ready to meet with the gymnast, goes to a summer camp at the college, then that's all completely within the rules.
The top 15 or so ranked colleges have their rosters 4-5 years in advance, actively recruiting and verbally committing stellar 8th-10th graders (but mostly 9th) who have made it to nationals and whose names are well known. But the bottom half ranked colleges and the D2 and D3 colleges do recruit girls who don't make it to nationals. That means the gymnast families and their coaches need to do the leg work - sending out feelers, emailing websites, youtube channels, etc. in their early high school years, maybe even before if there are special circumstances. No it doesn't have to be public but sooner or later, if the gymnast competes in college, it will be out there anyway.