Barely two days ago the OP made what appears to be a sincere query.
Less than 24 hours ago the discussion of that query was abruptly diverted with posts, literally, from the perspective of confessed stupidity (with sarcasm or rare glimpse of honesty? the former intended but the latter revealed?).
Jeopardy answer: persona posting to provoke negative reactions.
Correct question: may be either the descriptive term or an individual example ("what is . . . ," or "who is . . . . ")
Beyond the provocations, more disconcerting (and in effect more disruptive) are contrasting reports which are blatantly implausible but which might be confused, by casual readers seeking real information, for sincere accounts of actual experience.
But nb8285 is correct, this is an anonymous Internet posting forum, and it is what it is, such diversions to be expected, best ignored.
Meanwhile, on the topic of what suffices as a Travel Document facilitating travel to Canada:
Most international airlines require a passport to board international flights, with exceptions for flights between certain countries. In particular, a passport is required to board a flight destined for North America from outside North America.
That is separate from what is required for entry into a particular country, including Canada.
Moreover, there are additional requirements for boarding flights destined for Canada (similar to those destined for the U.S.), such as that the airline check boarding passengers for authorization to enter Canada. Technically, Canadian PRs are required to display a valid PR card or a PR Travel Document; practically, there are many reports that PRs carrying a visa-exempt passport will be permitted to board flights destined for Canada simply by presenting the visa-exempt passport.
Reminder: authorization to enter Canada is not the same as actual permission to enter Canada. PRs have no concerns in this regard. PR status mandates permission to enter Canada. Technically all a PR needs to show at the POE is proof of identity and PR status, but practically proof of identity also establishes status. (In contrast, a Foreign National, someone who is not a "Canadian," as in neither a Canadian citizen nor a Canadian PR, may have authorization to enter Canada, such as a visa-exempt passport or a visitor visa, or work permit or study permit, but must still seek permission to actually enter and that permission is not guaranteed no matter what visa the individual is carrying.)
The problem the PR abroad can encounter arising from not having a valid PR card (whether expired or lost) is being allowed to board a flight destined to Canada.
Hence, all the discussion about traveling via the U.S., for a PR abroad who:
-- does not have a currently valid PR card
-- is not carrying a visa-exempt passport
-- but who has the capacity to travel to the U.S.
The PR who can get into the U.S. and who can travel to a land crossing POE on the Canadian/U.S. border, does not need either a PR card or a PR TD to obtain entry into Canada. All the PR needs to do is establish his identity (with status confirmed by the system).
So the problem for the OP can be solved, one way, if travel via the U.S. is possible, by traveling through the U.S. and reaching the Canadian border.
The other solution, obtaining a PR Travel Document, is impractical given the amount of time there is to make the trip, and given that being abroad without a valid PR card carries a significant risk of triggering a PR residency examination which, in turn, carries the risk of delaying the issuance of the PR TD; this is particularly true with the citizenship application pending.
All that said, the travel-via-the-U.S.-approach is not guaranteed to avoid triggering a problem. While re-entry into Canada is certain, once the OP reaches a land crossing POE, the absence of a valid PR card risks a referral to secondary at the POE, and again with the citizenship application pending there is a significant risk of further inquiry, potentially including the cancellation of the scheduled oath.
Otherwise, the technicalities regarding what suffices as a Travel Document for travel to Canada are just that, technicalities. It is, of course, often worthwhile to clarify the more technical aspects, such as that the report above suggesting that a PR card is not valid for travel to Canada from the U.S. since 9/11 is simply wrong (and both arambi and I have reported numerous experiences confirming this in practice). Relative to this, there are different rules governing Americans and Canadian citizens for non-commercial, land-crossing modes of transportation (such as the enhanced drivers license). But these different rules, for Americans and Canadian citizens, appear to be not relevant to the situation confronting the OP.