SCv3020 and ESXi 5.5 hosts

Hi all,

We've recently purchased an SCv3020 to replace an ageing PS array in production. 

Our setup:

3 ESXi Hosts

 - Dell PE 710

 - Dell PE 720

 - Dell PE 720

Storage Cluster

 - Dell EQ PS4000 - Firmware 9.0.3

 - Dell EQ PS4100 - Firmware 9.0.3

The problem is with introducing the SCv3020 to the current infrastructure. I'm pretty sure I've configured it correctly, however no matter what method I use to link it to our vCenter it fails every time. Firstly, I've tried the Storage Manager Client 2018 R1.10.

First issue is it will only see 2 of our 3 hosts when I do this. One of the 720's is missing. But even with that aside, if I try to continue with any of the visible hosts I get the following:

So, well, that's infuriating. But when this happens a corresponding error appears in vSphere:

So I thought, alright. Lets try it a different way because this is now consuming WAY too much of my time. I tried the Dell Storage vSphere Web Client Plugin. It took me a while to find this, download it and get it set up.

Then to my utter disappointment, I saw this when I launched the plugin. My stomach dropped, again.

So that method isn't going to work.. I've no idea why the 'Summary' tab is greyed out. I can find NO information online and it's driving me nuts as this was all so straightforward with the PS series of devices, but with this SCv device there is just no explanation whatsoever and I'm only met with generic error messages or no message at all. What on earth am I doing wrong...