Girardi is currently at 3.6m, going down to 1.1 next year.
We have ~15 mill expecting to open up next seasson, this assuming one of the forwards get traded before the season. The only RFAs that need resigning are Georgiev and Nieves. Rangers have an expected 11 forwards under contract next season counting Kravtsov and assuming Boo is resigned. We have our entire D core filled, and many ELC contracts in Hartford waiting to fill any gaps that open up. So effectively, we have ~15m im space to resign Georgiev, Nieves, and then 2 more forwards assuming no more Fs are acquired via deadline trades. Nieves will likely be under 1m, and if hes not we can replace him with another depth player. Georgiev will get a bridge contract, comparables for his situation are around 2-3m on a short term deal (Grubauer, Hellebyuck).
So EVEN counting this dead space, we have 11m+ to sign 2 forwards to fill out the roster. Besides, we don't need to buy out both Shattenkirk and Smith, just shattenkirk should be enough to get Lemiuex and ADA.