[LMoP] Recognising Iarno from a description

[MightyAtom]

I have a question in regards to the whole Iarno / Glasstaff part of LMoP. The pre-gen rogue has a backstory that involves wanting revenge on Glasstaff after the Redbrands try and kill him. This to me says that he would have met him in person (at least in my mind) given that he was a member as well. Does this then mean he might recognise that Iarno is Glasstaff is Sildar gave a description of his friend before encountering with the party? How would you work this as a DM? (my current DM is a novice and might not realise this and so I would like to give some help given she's my wife).

Thanks for the advice.

Mighty Atom