The striker, a target for Newcastle United, missed Brentford's friendly win against QPR.
"The situation is clear: he's training at the training center," Andrews told Sky Sports. "It's probably already common knowledge that he left our training camp in Lisbon.
"I think it was the right decision for all parties involved; we must support him at a difficult time for him. Let's look beyond football; let's remember that before being footballers, we are human beings," the coach added. "It's well known that there is interest in Wissa. We must respect this situation and respect him as a person."
Andrews also emphasised the good relationship he has with the player: "I've had a good relationship with Yoane since last season, and it still is, but obviously it's not an ideal situation.
"We're in constant communication with Yoane about the situation. I think he's dealing with it well, but I understand it's stressful for him. I've been in a similar situation as a player: it's important that everything is handled with respect for people.
"Looking at this year's transfer window, the sales were made early. This is probably not what we wanted or desired, especially from my point of view. It's not an ideal situation, but that's the market."