Well, It may be worthwhile attempting to seek the origins of this man.
Born Yarmouth
Ship Rosaline, etc.
That way you could support the idea it is 2 seperate identities.
Worth bearing in mind that there was not only confusion in records, at times, but also wilful deception.
Not everyone wished to acknowledge a painful criminal past.
Your chap, as shown on the 1841 was, as you say, a forger,
Quite skilled. This old man was a labourer of no means.
Sue