Disclaimer: It is likely that there exist contrary opinions that I've neglected to include. CYLOR as usual.
Blessings on beverages exempting foods
Be'er Moshe (Vol. 1, § 11) states that, although foods and beverages are two distinct types (זה אוכל וזה משקה שני מינים מחולקים לגמרי), if someone intends from the start to consume both a food and a beverage, a beracha on either one can exempt the other. Yafeh Sha'ah (OC 17) agrees based partly on the Chida who writes that a person who only drank can exempt from a b'racha acharona a person who only ate (Birkei Yosef OC 213). The Yafeh Sha'ah writes that one need not prioritize a b'racha on solid food over a b'racha on a drink, and one might infer the same from the Be'er Moshe's treatment of the Magen Avraham and the Mishna B'rura.
Note that there are opinions, such as the Aruch HaShulchan (OC 211:17, וז"ל: ונ"ל דאכילה קודם לשתייה), that rule that a b'racha on food takes precedence over a b'racha on a drink.
Food with a known blessing exempting a doubtful food
The P'ri M'gadim (13 ,אורח חיים, פתיחה להלכות ברכות) writes that unless one specifically intends otherwise, a b'racha on a food requiring a more general b'racha might not exempt a food upon which there is a safek regarding whether it requires a more specific b'racha. Therefore, he writes, one should have specific intention that the b'racha cover the doubtful food:
ואני מסופק בפרי האדמה ודבר שיש בה ספק לפניו ובירך פרי האדמה בסתמא, אם פוטר הספק, דשמא דינו פרי העץ ובעי כוונה, או דילמא הואיל וספק הוה פרי האדמה ואין צריך כוונה, כי הוה כמו ברכותיהן שוות. על כן יזהר כהאי גוונא לכוין בפירוש
Elsewhere, the P'ri M'gadim rules that one need not prioritize a b'racha on solid food over a b'racha on a drink (Mishb'tzos Zahav 211:6):
ואכילה לשתיה אין בו קדימה אם ברכותיהן שוות רק בחביב ורוצה עתה
Therefore, according to the P'ri M'gadim, it would be acceptable to recite a shehakol on the coffee or tea with the intent that the b'racha cover the food as well.
Blessing on doubtful food exempting food with a known blessing
R' Ben Tzion Abba Shaul (Or L'tziyon 2:14:15) writes that if someone recited a more general b'racha on a food that should have a more specific b'racha, the general b'racha that was recited exempts other foods that require that general b'racha (subject to the person having intent to cover those other foods when he recited the b'racha). For example, if someone recited ha'adama on a pear and intended to also eat a potato, his b'racha covers both foods:
אם טעה ובירך בורא פרי האדמה משום שחשב שפרי זה ברכתו בורא פרי האדמה, יכול לאכול שאר פירות האדמה שבדעתו היה לאוכלם כעת, אבל שאר פירות העץ לא יאכל בלא ברכה
(Note: This only applies if the b'racha was made intentionally; if ha'adama was recited due to a slip of the tongue, and the person meant to recite ha'eitz, he may eat other ha'eitz fruits that he had been planning on eating, but "it is better that he not eat ha'adama vegetables unless he first exempts them with a blessing on a ha'adama food he did not originally intend to eat.")
בנידון דידן : In terms of whether a shehakol on the doubtful food would cover a drink like coffee, if the food is clearly solid, you would require specific intent anyway for the b'racha to cover the coffee since the items are two distinct types (שני מינים מחולקים). It seems to me that this would be sufficient to cover both items even though the appropriate b'racha on the food is doubtful, a fortiori since there is reason to permit reciting shehakol l'chatchila.
(Consider, for example, the case of a banana, about which the proper beracha is doubtful. Because of the doubt, we recite the more general borei p'ri ha'adama (Shulchan Aruch OC 203:3; see Mayim Chayyim 54 who explains this as the rationale for the Shulchan Aruch and incidentally rules on this basis that shehakol is the preferable beracha in this case of doubt)).
Blessing on ground fruit
As far as the correct b'racha for the partly ground fruit in question, the following is from here:
If one grinds a vegetable or fruit, whether or not one cooks it, if the vegetable is still recognizable in the product then the Bracha is the same the vegetable, however if it’s ground and unrecognizable then the Bracha is shehakol.
The Gemara Brachot 38a concludes that the Bracha for Tarima (processed dates) is HaEtz because the actual fruit remains. Rashi (D”H Tarima) explains that Tarima is dates which were crushed but not pulverized. However, Rambam (Brachot 8:4) explains that even if one removed the pits and crushed it and kneaded it into a dough the Bracha would still be HaEtz. The S”A 202:7 rules like the Rambam and the Rama rules like Rashi.
The Mishna Brurah 202:42 concludes that whenever the fruit is recognizable (because of the form and texture) the Bracha would be like the fruit, however, when it’s so processed that it’s not recognizable the bracha is Shehakol. Vezot HaBracha (pg 100, chapter 12) and Veten Bracha (Halachos of Brochos by Rabbi Bodner pg 403-4, chapter 22) agree.
However, the Laws of Brachos (Rabbi Forst, pg 303-5) explains the Mishna Brurah as saying that even for an unrecognizable pulp one should make the bracha of the original fruit. Only something which completely lost it's solid form is shehakol. He therefore writes that apple sauce is HaEtz, and mashed potatoes and peanut butter are HaAdama.