Gibbes is rated as having only a 50-50 chance to face the British & Irish Lions in Hamilton next Saturday after suffering a foot injury during the Maori's 29-27 win over Fiji in Suva.
"Jono Gibbes has a problem in his foot area and he needs a scan when we get home [to New Zealand]. So that is a bit of a concern," said Te Pou.
"It will be huge to lose him. He is our captain and is very experienced and has a lot of mana (respect) within the team."
There is better news regarding Sean Hohneck, who missed the Fiji match with an infected elbow. The lock is expected to be fit for the Lions game after having the area cut and cleaned out when the infection did not respond to antibiotics.
Te Pou has also named fly-half Carlos Spencer and flanker Wayne Ormond in his 22-man squad. Spencer missed the Fiji match because of his involvement with Martin Johnson's testimonial game at Twickenham, while Ormond was released so he could lead his Bay of Plenty side against the Lions.
Te Pou stressed however, if Spencer was included in the Maori starting XV next week it would not be a decision based on sentiment despite the fact it will be the mercurial fly-half's final match in New Zealand before his move to Northampton Saints.
"First we will be focused on the fact that we want Carlos to come through [the testimonial match] without an injury. He played extremely well for the Barbarians against England.
"When we select the XV it will be the best XV on performance. Carlos is up for selection and all going well he will come through this [testimonial] game well."
The Lions will face the strongest Maori team Te Pou has been able to call upon in his 11 years as assistant coach and coach of the side with 12 players who have represented the All Blacks in the 22.
Aside from Spencer and Gibbes, boosting those ranks is the Crusaders quartet of Corey Flynn, Rico Gear, Caleb Ralph and Leon MacDonald, who were rested for the Fiji game, and Carl Hayman, Greg Feek, David Hill, Marty Holah, Daniel Braid and Piri Weepu.
"We came close [to fielding our strongest team] when we played Australia in 2001. We still had a couple of guys on duty with the All Blacks then but this time we had first call so they are all going to be in camp.
"It makes us feel good to have the best to play the best and we are looking forward to it," Te Pou said.
New Zealand Maori squad: Daniel Braid (Auckland), Neil Brew (Otago), Greg Feek (Canterbury), Ross Filipo (Wellington), Corey Flynn (Canterbury), Rico Gear (Nelson Bays), Jono Gibbes (captain, Waikato), Carl Hayman (Otago), David Hill (Waikato), Marty Holah (Waikato), Sean Hohneck (Waikato), Scott Linklater (Waikato), Deacon Manu (Waikato), Angus MacDonald (Auckland), Leon MacDonald (Canterbury), Luke McAlister (North Harbour), Craig McGrath (North Harbour), Wayne Ormond (Bay of Plenty), Caleb Ralph (Canterbury), Carlos Spencer (Auckland), Rua Tipoki (North Harbour) and Piri Weepu (Wellington).