Vulkan's Wrath Tartarus Defence

[Purplehood69]

Up until this scenario I was doing wonderfully.
I have tried this battle in numerous fashions and cannot defeat the continuous waves of Orks and heavy units that appear to reinforce the Horde.
I have had a defence extending along the trench lines covering all the Salamanders starting spawn points.
I have tried consolidating around one particular flank in the hope of defeating the horde and retaking lost victory points.
It is apparent I lack the tactical acumen to successfully accomplish this defence.
I respectfully request that anyone that has won this scenario lend me some constructive advice.
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Anyone played this scenario and won?
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[Bl00dyDruid]

I just finished it. Just held the line, and kept the enemy demoralized. Don't do anything risky, and keep your units helathy