The stand-off has confirmed he will leave Scotstoun to join Gloucester at the end of the current campaign, creating a large hole in the Warriors midfield.
Wilson had wanted to bring in a new fly-half at the start of the season before his budget was cut and he will now look to sign a couple, if finances allow.
The coach would not be drawn on potential interest in Ben Healy, the young Munster and Ireland under-20 stand-off who is Scottish qualified.
“There is nothing I can say until I can clarify, confirm or deny,” said Wilson, whose first season in charge of Glasgow has been beset by problems, most of which can be attributed to the pandemic.
The absence of supporters has cut income and seen his player budget reduced accordingly. The hastily arranged Autumn Nations Cup and delayed Six Nations clash with Wales extended the international window and deprived Wilson of his frontline players for weeks. Throw in an injury crisis and it’s no wonder the coach has been tearing his hair out.
“The whole season has elements of frustration for a whole host of reasons,” he said. “From Covid, budget, injuries, international release. All I can do is keep standing up and going again, standing up and going again.
“It is tough and in tough times you see the true character of people. We want to keep fighting despite the frustrations and difficulties. It is frustrating losing Adam as we wanted him to stay in Scotland and stay in Glasgow.
“He has developed really well and become a really good player and done well on the international stage and when that happens clubs will come looking.”
Wilson said he was not under orders to sign a Scottish-qualified replacement and was candid about the pros and cons of such a scenario.
“There’s the opportunity to sign non-Scottish-qualified,” he said. “The obvious aim for all of us, and part of my role, is to make sure that we bring through Scottish-qualified players to add to the talent pool and to the depth that Scotland needs to create.
“But let’s be honest about it, when you do have Scottish internationals, this season anyway, they’re away for a huge, huge portion of the season.
“It’s a Catch-22, isn’t it? If you fill your squad with Scottish internationals, that’s brilliant for the big picture, which we all want to support. But it’s also very, very tough for Glasgow during those periods as we’re seeing right now.”
Hastings, who began his professional career at Bath, wanted another crack at the English Premiership and will head south after four seasons at Scotstoun.
The 24-year-old said leaving Warriors was an “extremely tough decision”.
“Glasgow made a very good offer and I absolutely love being at the club and with the boys here,” he added.
Hastings injured his shoulder playing in the win over Wales in October and will likely make his comeback during next year’s Six Nations.
“He will play for Scotland first in terms of his route to recovery,” said Wilson. “When he comes back he will play passionately for Glasgow, I have no doubt about that.”