It is plausible, but fairly unlikely unless SNP lose a constituency seat or two I think. On the last results, if you halved the Green vote and gave the extra all to the SNP then SNP would have been able to take the 7th list seat but much less wouldn't swing it and that does depend on it going all to SNP.
If it reduced by say 40%, with that going 3/4 SNP 1/4 Labour then the greens would still get a seat on about 12.3k
I'd love to see the little weasel out on his arse, just not getting my hopes up