with wildcard DND doesnt it have to be on the same server then
Alternatively, as you suggested, you can run multiple installs of echophp, which will cost a good deal more money.
Those multiple installs may reside on separate servers, but any domains tied to them must reside on the domain's server.
I'll give you an example:
I run 2 phpbbmf servers myself, on two separate domains. I do this because I'm running both phpbb2 AND phpbb3
Domains (and subdomains) tied to install 1 (phpbb4free.org) can reside on one server, but ALL domains tied to install 1 must remain on the same server as phpbb4free.org
Domains (and subdomains) tied to install 2(geekgas.com) can reside on one server, but ALL domains tied to install 2 must remain on the same server as geekgas.com
This isn't software related, it's DNS related. You need to have all wildcard entries pointing to the same ip address, otherwise, where is anything going to go? Seriously, you're confusing the situation by trying to put 'wildcard' on two separate servers like this.
Now, mysql, you'd better believe it can be put onto another server (it's about time we get that done, echo!). It should be easily rotated, that's not that hard to do. Wildcard DNS structures? Not going to happen.