1. I think yes. Assuming this is just PRNAV/RNAV 1 standard STAR, approved in your OPS spec. RF leg is no different to an DME arc if navigated with onboard NAV. I believe your aircraft is fully capable of doing this, though some other's RNAV boxes may not - hence the note.
2. No, since your training (reason to ask) and operational oversight (colleagues unaware) had obviously been insufficient.
no offence intended.