TorGmatGodShort answer: no, not necessarily.
First, it's important to note that since modifiers are not verbs, they don't have a tense. So we can't say that a modifier is itself in the past or present tense, even if it includes, describes, or modifies past or present actions.
Second, modifiers have a number of different uses and meanings, so we need to think about them flexibly. For instance, if we use a present participle (-ing form) as an adverbial modifier, it may describe why/how something happened, or it may describe a result that occurred later. Noun modifiers are a little less flexible, since they just attach to a noun, so they will usually just tag along with the time frame the noun is in.
A few examples:
An urban legend circulating when I was in high school was that Pop Rocks and Coke were a lethal combination. (Here, "circulating" is a noun modifier. Since the action takes place in the past, we know the rumor was circulating at the time I was in high school.)
Candidates applying in Round 3 should not get their hopes up. (Here, we're making a recommendation, so while we're talking about the future, it's not about any particular time. It's more of a general statement. The word "applying" is a noun modifier for "candidates." We're talking about any time a candidate applies.)
Wanting to make a good impression, I prepared extensively. (Here we have an initial adverbial modifier. I prepared because I wanted to make a good impression. Clearly, I must have wanted this before I prepared extensively, but this isn't a matter of order or simultaneity. I probably wanted to make a good impression both before, during, and after my extensive preparation.)
In 2021, I found a cure diabetes, eventually earning numerous awards for my breakthrough. (Here, the adverbial modifier comes after the main clause and shows a result. It's clear that the awards came after I found the cure in 2021, but we don't know exactly when. Later that year? 2025? Spread out over 30 years? We don't know, and that's not a flaw in the sentence.)
The festival we have planned will consist of about 30 shows at outdoor venues, culminating in an all-night jam session on New Year's Eve. (Here, "culminating" is an adverbial modifier applying to the previous clause, showing what will happen in the future, at the end of the festival we have recently planned.)
-Ed words can work like -ing noun modifiers, but they too won't necessarily stick to one time frame. For instance, we could say this:
Considered the world's leading expert on moths, Dr. Chandra spent much of her childhood looking through a magnifying glass at the creatures in her neighborhood. Here, it's clear that Dr. Chandra is
now considered the leading expert, and this may have been true for some time, but the action described in the main clause clearly predates that status.
So . . . it's complicated.

So, getting to your question in #2, there's no indicator that this noun modifier for "deal" is talking about the future. If the deal has just happened, why would we interpret "making" as happening in the future? Also, note that the noun modifier "a part of a deal" would apply to the noun phrase "$950 million," so we want to throw this out before we even get to the -ing modifier.