I disagree, there's not a whole lot of pressure for the Flames to rush a trade when the deadline is still a little ways off. Granted, there's the risk Tanev gets hurt, but there's also a better likelihood of teams getting more desperate as the deadline approaches.
The Flames may not be all that keen on helping the Leafs after Treliving left, but I do believe they're more than willing to hose them for a 1st if they can get one. There's a solid chance they could too tbh, As of today the Leafs are 7th in the East with 62 points, they have Detroit (60), New Jersey (58), and New York (57) on their tail. The Leafs missing the playoffs would be considered disastrous. Philly's also been sliding but should be in the mix around the fringes, they're two points ahead of the Leafs.
Dallas is supposedly amongst the teams interested in Tanev too.
The Flames know they can get a 2nd+, it's not a matter of whether they can or not, more than likely they're holding out to see if they can get a 1st.
I don't think it'll come down to being equal, Conroy has to get the best return he can for Tanev, period. Tanev has little control over his destination beyond his 10-team NTC. Flames are looking to retool more than rebuild, they have to hit a home run with this trade.
Short of them trading Hanifin prior to Tanev it's likely the Flames will set the D market with a Tanev trade.