decision making
You are correct XNR in that filing to a point in space is LEGAL as your destination.
HOWEVER..... WHY?????
Are you trying to just " get the job done" at all costs... in this case, putting you and the people you are responsible for into a situation without options(i.e... you must make your "alternate" given that it is your real destination).
Given that your helipad is in proximity to the "alternate" airport, basic pilottage tells me that the same weather system will probably prevail over both areas...helipad and a/p.While you are legal to file as stated, your decision making is VERY questionable!!!!
I realize that filing as stated saves gobs of fuel req'd and is technically legal, but as a very experienced mountain pilot taught me....... WHERE IS YOUR WAY OUT!!!!