PS: And let us know how it goes!
I’ve somewhat solved this with some apache rewrites. I’m convincing the customer to switch to subdomains in the future, and added;
RewriteRule ^path1(.*)$ http://subdomain1.domain.tld$1 [L]
RewriteRule ^path2(.*)$ http://subdomain2.domain.tld$1 [L]
I attempted to keep the address bar the same by having these rewrites passed to mod_proxy via the P flag, but WordPress was extremely unhappy with that.
Even with multiple networks I’m unable to modify the new network to be a subfolder install. Is there a way to define SUBDOMAIN_INSTALL on a per network basis?
Using networks for wordpress I was able to setup the second site, however there was no prompting and seemingly still no option for blogs to be hosted off of a subdirectory?