It appeared Koeman was on the brink of being sacked prior to Barca's 2-0 defeat to Atletico Madrid on 3 October (AEDT) and a 3-0 Champions League loss to Benfica suggested his fate was certain.
However, president Joan Laporta opted to stand by the former Everton boss as he acknowledged the difficulty of managing injury problems and the loss of Lionel Messi amid the club's financial crisis.
Midfielder De Jong moved to defend his side in recent days, insisting the team's issues were "exaggerated a lot" and that their season was far from a write-off.
Netherlands boss Van Gaal delivered two LaLiga titles, a Copa del Rey and the UEFA Super Cup in his first spell as Barca coach, but he endured a difficult relationship with players and supporters at Camp Nou.
Van Gaal said he was not surprised to see his compatriots being criticised.
"If everything is going smoothly, and you have great contributions that Frenkie has made in the past two years, then there is nothing to worry about," he told reporters.
"But when things go bad, people at Barcelona always look at the foreigners. And in this case, the coach is also a foreigner and a Dutchman.
"I have experienced that, too. History repeats itself. But I think Frenkie handles it very well, and Ronald, and Luuk de Jong and Memphis [Depay], too. I don't think that's the biggest problem.
"At the moment, they are trying to do everything they can. I've never had a striker like Memphis who runs so much, comes so deep and gets on the ball so much. That's commendable."
The Netherlands' 1-0 win over Latvia put them two points clear of Norway in their World Cup qualifying group.
Victory over Gibraltar, who have lost all seven of their games in Group G, would put Van Gaal's men in a strong position to qualify for Qatar 2022.