There would be several issues associated with this question.
Online:
One is the domain, i.e., *advertiser censored*.com that is the internet location of the online fountain site. This domain is always registered to an owner. IIRC, Dan registered the domain in his name early on when he was helping Joseph set up the site. That became an issue later on when they had the falling out and DK threatened to take down the site, etc. Because the domain was registered in DK's name, he had the ability to sell it, let it lapse or whatever. Even without the domain registration in his name DK could have intentionally disabled the site leaving Joseph with little to do rather than take DK to court or start over with a new domain and website construction if he couldn't come to terms with DK.
You then have the actual online website called "EIP" -- Joseph's earlier online effort consisting mostly of drop-shipped items. I believe DK was the webmaster. As such he would ostensibly take care of technical issues and other matters regarding the site's operation. He was also Joseph's SEO go-to (search engine optimization) meaning that he was responsible for increasing traffic to the site by various means (not worth getting into here) but designed to increase sales by increasing the number of people visiting the site. The site had had a shopping cart system to process the sales through whatever means Joey provided to customers, i.e, PayPal and/or common credit cards.
Custom:
As we know JM also had an increasing business in custom designed water fountains, also under the name of EIP and wholly or predominantly a different animal than the online business. It is this side of the biz where CM enters the picture, and why DK and CM didn't really associate with one another. This side involved physically designing the water features, buying the necessary supplies, assembling and shipping and often reassembling onsite. It was also becoming Joey's most profitable and demanding business efforts, and how he became fatally involved with CM. Why we are here today.
Chaos:
Since all of JM's business seemed to be operated as a sole proprietorship, it appears that all financial decisions and actions quickly became ad-hoc when Joey disappeared. There was no one in Joey's family even remotely qualified or able to operate the online business. Thus, it's easy to see that DK, legally or illegally was the only one alive, really, to help or hinder the online efforts. It seems, IMO, that he did a little of the former and quite a bit of the latter. Mr. Jitty has explained some of the legal principles involved, but in essence, without a strong corporate structure and minus Joey, the online EIP quickly became anybody's game - or so it seemed. It left DK with complete physical (not necessarily legal) control of the online business, that resulted in several apparent buyer scams, possibly fraudulent withdrawals, and ultimately a self-serving sale of the entire operation. The family, I'm sure was at a loss to deal with the intricacies while at the same time in a panic over the missing family.
Sorry for the long-winded account, but some folks seem confused over a fairly confusing business set up.