Yes. Ikelite housings have historically locked you into ikelite strobes. I am unsure about the new ikelite optical strobe connections. They may support non-ikelite strobes? Some one who knows more than me may be able to answer this.
Background info:
Otherwise it is generally mix and match except some models of strobes do not work with some models of cameras. The strobe manufacturers generally provide a list of supported cameras.
If you want to use fibre optical sync cables, then there are a few different "housing connectors". this just means you need to buy or make a fibre cable that will connect to both the housing and strobe.
If you want to use wired sync, then you need to ensure you have the proper bulkhead connector and the proper cable. Not something you need to worry about with your choices.
Your world:
The megagear housing
MegaGear 130ft 40m Underwater Waterproof case Housing with Floating Wrist Strap for Canon PowerShot G15 WP-DC48: Amazon.ca: Camera & Photo appears to be a rebranded meikon housing (or maybe meikon is the rebrand?). The housing supports 2 standard sea & sea (or olympus or nikon) fibre optic cables. You should be able to use any compatible Sea & Sea or Inon strobe. Lots of choice.
P.S. the link to the housing i provided above has a stupid price: CDN$ 2,501.74. Something is wrong. This line of housings should be less than $200 US.