To answer my own question, it looks like there's not enough cap to protect Dell from waivers, unless we send someone like Barabanov down and try to squeeze Dell onto taxi squad (waivers) after the season starts.
Edit: but that would mean starting game 1 with 11 forwards and 7 D so I doubt they do that.
CapFriendly.com Armchair-GM User-Generated Roster
FORWARDS (12)
Right wing: Mitchell Marner ($10,893,000) - William Nylander ($6,962,366) - Ilya Mikheyev ($1,645,000) - Wayne Simmonds ($1,500,000)
Centre: Auston Matthews ($11,634,000) - John Tavares ($11,000,000) - Alexander Kerfoot ($3,500,000) - Jason Spezza ($700,000)
Left wing: Joe Thornton ($700,000) - Jimmy Vesey ($900,000) - Zach Hyman ($2,250,000) - Alexander Barabanov ($925,000)
DEFENSE (6)
Right: TJ Brodie ($5,000,000) - Zach Bogosian ($1,000,000) - Justin Holl ($2,000,000)
Left: Morgan Rielly ($5,000,000) - Jake Muzzin ($5,625,000) - Travis Dermott ($874,125)
GOALTENDER (2)
Frederik Andersen ($5,000,000) - Jack Campbell ($1,650,000)
AHL BURIED (1)
Pierre Engvall ($175,000)
BUYOUTS (1)
Mikhail Grabovski ($0)
RETAINED SALARY TRANSACTIONS (1)
Phil Kessel ($1,200,000)
DETAILS
Roster Size: 20
Salary Cap: $81,500,000
Cap Hit: $81,058,491
Cap Space: $441,509