Bris Milah
The Shulchan Aruch says in Yoreh Deah סימן רסג - ילד שהוא אדם או ירק, ומי שבניו מתים מחמת מילה that when doing Hatafas Dam Bris one does not make a Bracha - unless one is certain that there's some hint/remnant of the Orla.
ד נוֹלַד כְּשֶׁהוּא מָהוּל, צָרִיךְ (ב) לְהַטִּיף מִמֶּנּוּ דַּם בְּרִית
באר היטב (ב) להטיף. ואין מברכין על המילה אא''כ נראית לו ערלה כבושה
Hatafas Dam Bris is not done on the 8th day - rather one waits until the child is old enough to safely undergo the procedure, as it states ibid:
וּמַמְתִּינִים לוֹ הַרְבֵּה וְאֵין חוֹשְׁשִׁין לְיוֹם שְׁמִינִי, שֶׁלֹּא יְבִיאוּהוּ לִידֵי סַכָּנָה.
The question remains as to whether Hatafas Dam Bris is needed at all. The Shulchan Aruch in Yoreh Deah סימן רסד - מי ראוי למול says that a non-Jew must not do the Bris, but if he did there's no need to do it again.
The Remo argues/adds that "some say that Hatafas Dam Bris is needed - and that's the main opinion".
אֲבָל עוֹבֵד כּוֹכָבִים, אֲפִלּוּ הוּא מָהוּל, לֹא יָמוּל כְּלָל. וְאִם מָל אֵין צָרִיךְ לַחֲזֹר וְלָמוּל פַּעַם שֵׁנִית. הגה: וְיֵשׁ אוֹמְרִים דְּחַיָּבִים לַחֲזֹר וּלְהַטִּיף מִמֶּנּוּ דַּם בְּרִית. (טוּר בְּשֵׁם סְמַ''ג) . וְכֵן עִקָּר.
The Remo also mentions that - in the case of a baby had a bris before the 8th days (for medical reasons) - then if some the Orla remains or the Pri'a wasn't done, then the baby should have a second Bris. He doesn't mention what to do about the Bracha.
מִיהוּ אִם נִשְׁאֲרוּ צִיצִין הַמְּעַכְּבִין הַמִּילָה, אוֹ שֶׁמָּל וְלֹא פָּרַע, יִגְמֹר הַיִּשְׂרָאֵל הַמִּילָה לְח' אוֹ לְאַחַר שֶׁיִּתְרַפֵּא (רַשְׁבָּ''א)
Best would be to get an expert Mohel to ascertain if the baby had a Bris or a medical procedure. If the latter, you also have to find out if it was done correctly to qualify as a Bris.
If it wasn't then it has to be redone.
If it was then you then have to figure out if you Pasken like the Shulchan Aruch (like most Sephardim usually do) and then you have nothing to do, or you Pasken like the Remo (like most Ashkenazim usually do) and then you need to do Hatafas Dam Bris without a Bracha.
This article had some good sources.
Pidyon HaBen
The Shulchan Aruch - Yoreh Deah סימן שה - מי חיב בפדיון בכור, ומתי ראוי לפדיון, וכל דיניו Paskens that if one is uncertain if a Pidyon is needed, then one is exempt.
מִי שֶׁהוּא סָפֵק אִם הוּא חַיָּב בְּפִדְיוֹן, פָּטוּר, שֶׁהַמּוֹצִיא מֵחֲבֵרוֹ עָלָיו הָרְאָיָה
The reason being that Pidyon HaBen is treated like a monetary obligation, and in monetary issues one is exempt from paying if both sides are unsure.
So much so that if one isn't sure who the father is, then the son has to redeem himself when he grows up, but the "fathers" are exempt.
וְכֵן מְבַכֶּרֶת שֶׁלֹּא שָׁהֲתָה אַחַר בַּעֲלָהּ ג' חֳדָשִׁים, וְנִשְּׂאָה וְיָלְדָה זָכָר, סָפֵק בֶּן ט' לָרִאשׁוֹן אוֹ בֶּן ז' לָאַחֲרוֹן, הָאָבוֹת פְּטוּרִים, וְהַבֵּן חַיָּב לִפְדּוֹת אֶת עַצְמוֹ
So in the case you mention, even if you know for sure that the boy isn't redeemed you wouldn't be obligated to redeem him. If he can ascertain that he's a firstborn valid Bechor when he grows up he'll have to redeem himself.