Police were going to attempt to trace Mr Wyatt's banking records, but public holidays have delayed getting his banking details from the United Kingdom.
"And his banking literature is on his laptop, which is locked and is flat," Mr Cogger said.
"We're still trying hard, you've got to keep going and going and going."
In the area Mr Wyatt was tramping, he had two options of paths to travel, either towards the D'Urville Valley or the Waiau Valley, Mr Cogger said.
Searchers were also hampered because Mr Wyatt failed to fill in log books at Department of Conservation huts, "so we've got no real starting point".
He had a back country pass, which meant he could have stayed in any of the huts for free, so there was no reason not to fill in the books, Mr Cogger said.
Police knew Mr Wyatt's planned route, but his plan was decided in November and weather could have changed tracks in that time, he said.
Mr Wyatt was last seen by a tramper at Blue Lake in Nelson Lakes National Park on or about December 14.
He was intending to tramp to the Boyle Village in Lewis Pass, where he was due to pick up a food package on December 16, but he never arrived.
His intention was to then carry onto Arthurs Pass where he had another food parcel to collect, police said.
Police have been in contact with his parents in Cornwall, England, who said they had not heard from him since December 12.
They were also keen to speak to anyone who was tramping in the Blue Lake, Sabine Valley, D'Urville Valley area of Nelson Lakes National Park between December 13 and 19.
Mr Wyatt is 180cm tall, with ginger hair and was carrying light equipment.
Contact Nelson Police on 03 546 3840 urgently. The Police event number is P015791441.