The biggest problem I have is them giving me a deadline and then completely ghosting without dropping in to let me know that's it's been pushed back. I've waited over a year for a (digital) commission before and had no problem because the artist kept me in the loop (and had a Trello for updates) and never had a set deadline, so waiting isn't a problem itself.
I was given a deadline for the sketch/WIP, waited a week, and sent them a message, to which I didn't get a reply to nor has it been read. I get the last seen feature on Toyhouse isn't incredibly accurate but all I have to go off of is that feature. No other social media is linked on their page or commission thread, and activity in the forums means very little when I sent a PM (and the last activity in the forums was over three weeks ago, before I even got the message with the deadline).
I'm going to wait until around the 27th because that'll be two weeks since I sent the PM, then I'll message them again to see what's up and if everything is alright. I'll refrain from using the email linked to their PayPal until I absolutely have to though because that's kind of an invasion privacy unless they explicitly said it was cool to do.