They recite etc. - Even if a long time passed after relieving themselves, they still need to recite the blessing. If one did not recite Asher Yatzar before needing to urinate again - the opinion of the Pri Megadim is that before urinating, one should recite the Asher Yatzar blessing for the first urination. But Shaarei Teshuva agrees with several Achronim that if one remembered after he started to feel an urge [to relieve himself], he should not recite the blessing. See there further.

Asher Yatzar - Maharshal, in responsa siman 97, wrote that someone who ate something that requires an after blessing and forgot [to recite it], and then urinated, then remembered it before reciting the Asher Yatzar blessing - which of them takes precedence? He replied that Asher Yatzar comes first since it's more frequent. One who drinks a laxative, wherein he has in mind from the outset to empty his bowels completely - there is an opinion that he should only recite the blessing [once] after he has finished; there is another opinion that he should recite the blessing each time he goes. The common practice is like the latter opinion. However, if it is a heavy diarrhea, where he feels an urge immediately after the first time to go again, it is prohibited to recite the blessing then as is seen below in siman 92, [for in that scenario] even learning Torah is forbidden [Shaarei Teshuva].

Pray immediately - Even though we established in siman 233 se'if 2 that for the afternoon and evening prayers, even if one is not aware of any dirt [on his hands], he must wash his hands [before praying], and certainly [he must wash] after relieving himself, nevertheless he only recites Al Netilat Yadayim in the morning. See Artzot Hachaim who wrote that the opinion of the majority of Poskim is that if one defecated and afterwards wants to pray, he must recite Al Netilat Yadayim. Nevertheless, a priori one should not veer from the ruling of the Shulchan Aruch. See further in Maasei Rav.

Because he wiped with them - The drops of urine. The same applies to when defecating, where he relieved himself and then wiped himself.

For [the sake of] cleanliness/hygiene etc. - If one does not have water to wash with, he still must recite the Asher Yatzar blessing. Even if he wiped himself, it's implied above, at the end of siman 4 in Magen Avraham, se'if katan 28, that for reciting a blessing, it's enough to wipe one's hands on anything that can clean them.

Twice - Like we find regarding prayers - that if one erred and didn't daven shachris, he davens mincha twice. But many of the Achronim argue on this ruling and they hold that prayers are different since they are in place of sacrifices, and [missed sacrifices] can made-up for; as opposed to Asher Yatzar, which is a blessing of thanksgiving, one can fulfill his obligation with one thanksgiving on many occurrences, like one who ate twice and diverted his mind between the 2 eating's, he recites Birchas Hamazon once over both of them. And one should be lenient regarding a doubt [one has regarding] a blessing. Ideally one should be careful to recite Asher Yatzar immediately after urinating since maybe he will need to urinate again afterwards. The same applies to defecating.