Rafael has some great guidance - one would have hoped that your web team could have brought those forward.
Most importantly make it be a team issue and a team win, ultimately both are right to a certain degree and both own the solution. Hopefully the team sees the value in marketing automation and what it will do for your organization, so they can offer up solutions that help you mutually achieve your goals. Maintaining the website as is won't grow revenue, find a way for them to help enable the path forward
One of the simple things we do is use Marketo forms, but present them in our corporate site through an iframe - not that it is the best solution but I can see for you where the web team can build the pages but you can control the Marketo logic associated with the form - all the while presenting one view of the site, one search, etc. This helps with content repurposing, translations, and a myriad of other things we work with.
I'd also suggest doing a deep dive on why the other quick pages are being built, there must be a need that isn't being met. Again, challenge them to help meet the need - e.g. build a limited nav template that focuses on conversion. The new marketing environment is blended, web, MA, CRM, SFA - none of these will be successful in a silo.