Can an identified IFR flight I'm talking to merge with an unidentified VFR flight unverified altitude (but altitude is at least 1000ft difference)?

Dingle

Newcomer
Nov 13, 2021
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0
1
I've been told

1. they can merge because the altitude is there
2. They can merge, but you have to give traffic and "targets appear likely to merge, would you like a vector?" and if they request one, you vector.
3. VFR altitude is unverified, keep them separated.

Class E airspace.

I do #3, but have been criticized by either the trainer or sometimes the pilot will tell me "you just said that aircraft is 2,000' below us, why are you vectoring us?" "That aircraft's altitude is unverified" "Well, we have it in sight now"