Montour is a UFA at the end of the year so I'm not sure they would select him.

Ufa are exempt from the list unless they resign before the draft

They're not exempt, but it's a bad idea to select them since they could easily walk two weeks after the expansion draft.

The expansion draft takes place 3 days after the new season begins meaning the players are officially FA however they are unable to sign until the FA period begins 1 week after the draft.

nhl free agency period begins in July, at least that is what happened in 2017 vegas year when expansion draft happened before july

I believe that you are mistaken.

I’ll double check but this little clause is what helped the sharks protect like 4 extra players last expansion draft.

June in normal years right after the Stanley cup is the start of the new fiscal year for hockey, but the FA signing period is first week of July, that’s means that FA are no longer employed by any franchise, however they are not allowed to sign until the FA window opens. I could be mistaken, however I know this is how the sharks protected like 4 players from the expansion draft ( they all resigned after the draft before FA began)