Don't worry, it is grammatically wrong in Romanian too, this is one of those sentences written when Sebastian was drunk.. :P
Correct in Romanian is either „O să vin mâine la tine acasă” or either „O să vin mâine pe la tine pe acasă”. Both mean the same thing, I will come tomorrow to your house/home. The ”pe” here gives the idea of passing by, not coming to stay, it is a way of making the ”self inviting” look more polite, like in ”i will visit you just a little bit”. Compare: ”soacra mea vine mâine la mine” (my mother in law comes tomorrow, it can mean for a minute, or to stay forever, god forbid...) and ”soacra mea vine mâine pe la mine” (she is just passing by, on the way to market, she may stay, but most probably not, god bless...). :))
The expression is a derivation from ”going through”, for example: ”voi merge în oraș” (I will go to/into the city) versus ”voi merge prin oraș” or ”voi trece prin oraș” which can mean the same, but textual is ”I will walk (or just pass) through the city”. The ”pe” gives an idea of moving to the static verbs. In fact, if you use moving verbs, like ”a trece”, the only correct form is with ”prin”, ”pe”, ”peste”, etc, ”voi trece pe la tine pe acasa” (I will visit you, I will pass through your house). Nobody ever says ”voi trece la tine acasă”. With moving verbs, use ”pe”, ”prin”, etc. You can omit ”pe” if you want to show the static side. ”Voi veni mâine la tine” can mean that I come to stay, not just to say hello.
So, here the idea is ”I will visit you for a short time, I will be just passing through your house”, and if you want to say that, you MUST use both ”pe”: Voi trece mâine pe la tine pe acasă. I.e. ”prin casa ta” (through your house, think to a wind, or a bullet).
This remembers me that joke with the railroad workers coming to evict an old guy ”linia ferata pe care o construim va trece exact prin căsuța dumneavoastră”, ”n-am nimic împotrivă, dar să nu vă închipuiți că eu o să stau să deschid și să închid ușa ori de câte ori va trece vreun tren”... (google translate is your friend, copy paste it with quotes too, for a better translation)