Slightly different scenario, but a friends DD wants to go into police. She is a bright girl, good academically, she had a place to do police degree last Sept but gave it up days before A level results as local forces were recruiting.
She got through to interview stage with one force, to be told, you are too young, go and travel, study, get life experience etc.
I thought she would re apply to do either a police or general degree, but no, she doesnt want to do a degree now, just police and is doing retail work in the meantime.
Hopefully she may get a civilian police job, she is also applying for those, but I can also see her just drifting. She is not the type to travel, although I appreciate that may change. At least going to uni would have focussed her for 3yrs, and given her a relevant degree.
My DS wants a certain career which is hard to get into but also doesn't need a degree (cant mention it here as, combined with above, it could out me) - he applied and got as far as interview last year during A levels. Didn't get in, so has gone to uni. He will apply again after uni, but hopefully with more maturity/life experience and if he never gets in, he will have his degree - also a science - to fall back on. He may even change his mind during his time at uni.
I was keen for him to go uni, rather than straight into his preferrred career, as I felt he would get so much out of uni experience and also didnt want him to narrow his options at 18. Although I did appreciate he could go to uni later if he had been accepted into career and it didnt work out.
So, I would say, let her go & do a Biology degree to start with then move into social work. Just doing an undergraduate degree can give her many life experiences, maybe even the opportunity to work/volunteer abroad which will help her in the future.