Sorry to hear you're still having a hard time!
I'm not at a gourami expert. But logically, along with trusting
@Slaphppy7 's opinion and the fact you've maintained this tank beautifully, and the issue only began when you lost the male, I'm inclined to agree that it's likely territorial/bossiness from one or more females causing the issues, that the male used to keep in line.
If you're having problems sourcing a male through the stores, I'd personally be looking for a male from other hobbyists.
@TwoTankAmin I know you're in NY, any suggestions for minding a male pearl gourami without buying from a dodgy online wholesaler?
Certainly where I am, there are a lot of fish rehoming groups on Facebook, specific to certain areas, but they're becoming harder to find as FB is stamping down on any trade of live animals on their platform. Mainly because of people buying and selling stolen or backyard bred dogs and cats, but it's affected any live animal trade, naturally.
But an ap called BAND may be useful, if it's available there, and I think it is. Can join fish hobbyist groups in your area, and try to source a male that way if you advertise that you're looking for a male. I can imagine anyone looking to rehome a fish would be delighted to home it with you in that beautiful set up!
I have a very skittish blue spot gourami female. But I got her from a neglected tank of fish I saw being advertised on Gumtree. The owners were moving and wanted to sell the tank and fish, I messaged and offered to adopt the fish, so they'd have an easier time selling an empty tank, and I'd provide a good home for their fish, or at least QT and get any I couldn't keep back to good health, and find good homes for those. They happily agreed, and gave me their single otocinclus, three spotted corydoras of unknown species (there are a lot of very similar looking corydoras!) the very pale and stressed female blue gourami, and a stunning, but adult, 6 inch rainbow shark.
I'd set up a 22g as a QT tank, but as soon as I added the fish, including the rock cave that they said the rainbow shark used and loved the most, the shark began to chase and harrass the blue gourami relentlessly, and she was terrified, nipped, and I got her out of there ASAP. I broke QT for her and added her to one of my large peaceful tanks, and while she coloured up and wasn't being harassed by a territorial rainbow shark anymore, she remained incredibly shy and skittish. I don't know how long she was stuck in a tank with that rainbow shark, but she's still shy, usually holds back during feedings until I've moved away, and dives for cover the moment anyone enters the room her tank is in, even more than a year later, and only living with peaceful fish.
Oh, after a month of quarantine and a lot of searching, I found the perfect home for the rainbow (beautiful as he was, I didn't have a tank that would work for that sort of fish, so couldn't keep him) the oto happily joined my gang of otos, and the cories were added to my group of 20 cories, and the blue gourami lives with them too.
I just provided a lot of hiding places for her, so she knows where she can dive behind and escape too quickly. maybe add some more hardscape, even if as a temporary measure? My girl often hides behind a bit chunk of driftwood I have in there, or dives into the thicker area of plants. If I slowly and gradually work my way towards the tank, and sit in the chair next to it without making sudden jerky movements for a while, she relaxes and comes out again. I'd put her skittishness down to her fear that she may be attacked by a rainbow shark at any moment - but perhaps it's more than that? I'll be thinking on it, anyway!