"The partnership with Companyname" vs "Companyname's partnership"

From a grammatical point of view, both sentences are correct English. There is nothing to choose.

That said, I would go with option 2. Option I leaves the speaker's own company or group outside the sentence. That makes it the passive recipient of advantages from the partner company.

While you are at it, "the partnership with" still leaves the speaker's group out of the active picture. That would be altered by replacing "the" with "our".

Finally, does the speaker only passively "hope" the benefits will accrue? Wouldn't "expect" be stronger?