Advice on workflow and CRM?

Hi everyone, I need some advice on setting up an extremely basic CRM. All comments welcome!

I have an employee whose job it is to reply to journalist queries. She does a great job of getting media mentions, but we could be getting more from the contacts she's developing.

I would like her to follow up with these journalists to try to get mentioned in the next article they write.

This is how I'd like it to go…

1. She replies to the journalist. Hopefully the journalist uses her quote.
2. She marks the contact as successful if we got a mention.
3. Wait 30 days.
4. If successful, send an email to the journalist saying "can I help with any articles you're writing?" Hopefully this will lead to another mention.
5. If the journalist replies to this second email, we reset the clock and wait another 60 days before emailing again. If the journalist doesn't reply, strike the journalist from the list and don't contact them again.

At the moment she's uses a really simple Google Sheet to figure this out. But she's not being consistent and the system just isn't working.

She's using a google email, so we should be able to link it into any CRM. It seems like a really basic functionality, but I just can't get my head around how to set this up. She's also not tech-savvy at all, so it has to be super-simple.

Any ideas on how to do this? Or at least which software we should be looking at?

Thanks in advance!!