As @t_bergman stated, phpVMS v4 can work on a shared hosting environment. It is not that difficult expecially if you are working on a linux environment and as soon as you provider provides you with SSH access.
Some web hosting providers require justification, some others offer it for a specific cost, others offer it for a specific period of time in order to monitor it. You are going to need SSH during the installation of the phpVMS v4 and in case you want to update your software. Afterwards, SSH is not required (as far as I know). Also, for cpanel, Jailed Shell can be enough.