The animosity between the Tories and the SNP has always been there, and is especially intense currently - as was obvious from Margaret Mitchell's approach to her questioning of Nicola Sturgeon - and with an election due I'm not surprised that the other parties are seeing an opportunity and taking it: after all, to use some local vernacular, the events around the Salmond situation are very much the 'talk of the steamie': for now.
Having conceded that they (the Scottish government) made a hash of the Salmond situation the key issue now is whether or not Nicola Sturgeon is deemed (via the other investigation) to have broken the ministerial code: if so, she may resign but she may decide to tough it out until Holyrood prorogues in around 3 weeks time, and if she is found to have not broken the ministerial code then she'll tough out whatever this committee reports until Holyrood prorogues - and at that point election campaigning starts.
The Tories may well use these events in their campaigning, but of course they are the party of Brexit and of Boris the Liar so while they are currently in attack-mode on a single issue (Salmond etc) they will have to deal with other matters during the campaign and Dross doesn't appear to me to be much of an asset to them, and he'll have to defend the SNP attacks on the Tory Brexit (we in Scotland didn't vote for either Brexit or for a Tory government), the Tories funnelling dosh to Tory-supporting areas, their undermining of Holyrood via their 'Internal Market' bill etc etc.
I'll be voting SNP, and I hope the Tories get trashed here.