Who is the boss?
You must have a sweet job in which you can accept or refuse work from some management structure.
The only jobs I get away with refusing are those in which my statement goes like this ... I need certain software or hardware tools to do this job which cost $ xx,xxx,xx & the company has not in the past seen fit to give me those tools ... now without those tools, I might be able to do the job in 2 years of doing nothing else ... so run your request up the management ladder ... is your need great enough to justify the $ xx,xxx.xx which has not been justified in the past ... or is it great enough to justify me doing your task without this & me do nothing else for 2-3 years ... and what happens is I am permitted to remain productive where I typically satisfy 2-5 user requests per day.
Now it is not unusual in big business for companies to launch stuff that does not work well with the rest of the enterprise's computer infrastructure, because the launchers were sold on something by an effective vendor & management not understand implications.
If you had been doing your job well, management would know why you do not think this will work, so when it fails, they turn to you as an expert, or get a second opinion to confirm your story. The risk is that this might send company into bankrupsy.
We happen to be on VPN on NT on Ethernet on AS/400 & it works great, but it was a big ordeal to get started because of all the ultra specialized vendors that were needed for all the pieces & they did not know squat about anything outside their area.
A company needs a vendor that knows the whole picture & spells out what training is needed for all the players to get up to speed.