Sooo I went through this last year. I was literally losing shots to vibration until I realized I needed a dedicated intervalometer for the 7DII. I've been really happy using the Vello ShutterBoss II Remote Switch with Digital Timer for Canon N3... it's super reliable. Basically, the N3's 3-pin locking design is way more secure than generic 2.5mm jacks. Quick tip: keep spare batteries cuz the LCD drains them fast!

Re: "To add to the point above: the signal..." yeah Lindsey is totally right about that wired stability. I really wanted the wireless dream to work for my 7DII, but honestly, it was such a letdown. Every time I tried a fancy remote, the signal would just... vanish right when the light got good. Not as good as I expected at all. After owning this body for ages, Ive realized those wireless units are just another thing to break or run out of juice. Sucks that we are still tethered to the camera for reliability, but that N3 connection is basically bulletproof compared to the alternatives. Just gotta be careful with the pins tho, they can be a bit finicky if you're rushing in the dark.

Been thinking about your setup and I have a quick question before I dive into details... how far away are you usually standing when doing that wildlife stuff? Like, are you right next to the tripod or trying to hide across the yard? I ask because reliability changes a lot when you go wireless. If you are standing right there, honestly nothing beats a hardwired connection for peace of mind. I have been super satisfied with these two for my 7DII over the years:

• Canon TC-80N3 Timer Remote Controller : This is the official one and it is basically bulletproof. The interface is a bit old school but it works every single time without fail. No complaints on the build quality at all.
• Pixel TW-283 N3 Wireless Remote Control : If you need range, this is a great budget alternative to the expensive ones. Its surprisingly solid for the price tho it eats batteries if you leave it on. Corded is usually better for landscapes cuz you dont have to worry about sync issues or signal drops when it gets cold out. Let me know about the distance thing and I can help you narrow it down further.

.

Exactly what I was thinking

This is exactly what I needed to hear. Youre a lifesaver honestly.

To add to the point above: the signal stability on a wired N3 connection is seriously unmatched! I love geeking out over the millisecond response times and the electrical contact reliability on those pins... it makes such a massive difference for sharpness when you are doing long exposures. Honestly tho, if you wanna see the real technical breakdowns and some awesome DIY mods, you should just hit up YouTube. Just search for 7DII remote shutter hacks or N3 intervalometer teardown and its like the top video. I watched this one guy basically build his own from scratch and it was fantastic! Seriously, just google it and check the first few Reddit threads that pop up, they have all the data sheets and wiring diagrams you could ever want. Its way easier than me trying to explain the circuit resistance here lol!