No, that is not the best answer they could have given.The best answer they could give you is "consult an electrician".
Put it this way, product manufacturer should specified how and what should be done, and the electrician would followed the instruction, he just make sure that something, for example, a GFCI outlet must be used when you plug your unit to one receptacle within 3' of a waterbody etc. The electrician doesn't detect how an electrical device should be installed, the manufacturer does!
It is fairly common knowledge that Growatt does not have the best customer service and that is why we buy from a supposedly reputable retailer vs ebay or Amazon. When the customer has questions, the retailer provides an answer, and if a suitable answer cannot be provided, the retailer acts as a liaison with the manufacturer until the questions are suitably answered.
As many of us have discovered, Growatt's manuals often lack documentation. Documentation that is critical for a diy installer, or electrician, to perform their job of safely installing certain units. Couple a lackluster manual with retailers who do not force the issue of attaining answers with their supplier, and we have the recipe for property damage, or injury.
The correct answer was for SigSolar to say we will contact the manufacturer and find out, or as @TURMIRE says, " ... that’s a good question, I’ll send our engineers a message and see if I can get get clarification. ".