Hi! I come from "Desire", another MN coin which is having the WATCHDOG_EXPIRED problem. I've build a standalone version of sentinel (it doesn't require any dependencies, namely python and so on, and can be run from a single EXE file).

This post is an adaptation of https://bitcointalk.org/index.php?topic=2272607.msg24594537#msg24594537

VIVO+ Sentinel standalone (windows + linux)

You only need to do this if you are running a masternode and getting "WATCHDOG_EXPIRED"

This is a version of sentinel that requires nothing but to run an exe, make you to follow all steps! Backup "wallet.dat" first, just in case

Download: https://github.com/ZonnCash/sentinel/releases/tag/v1.1.0-win64
Virustotal (3/67): https://www.virustotal.com/es/file/3a65c0df1fb89607531d8c02bb2a3070f1c39f555944d118c67d8ee616be5b18/analysis/1510697796/

Use at your own risk, it has been compiled exactly as the Github repo says

Before running it

1. Make sure you are running v0.12.2.1

2. Close your wallet

3. Go to vivocore folder and delete "mncache.dat" and "mnpayments.dat"

4. Make sure your "vivo.conf" contains, at least, the following data:
rpcuser=someuser
rpcpassword=somepass
server=1
rpcport=9998
rpcconnect=127.0.0.1

Try to make rcpuser and rpcpassword hard to guess, you won't need to remember/use them for anything else, so feel free to smash the keyboard

5. Open wallet. Resync the whole wallet, from the menu "Tools" > "Wallet Repair" > "Rebuild Index"

6. Make sure the wallet is running and completely synced before continuing

How to

To make it point to your vivo.conf, you have three options:

A) Create a file sentinel.conf in the same folder as the EXE with the following content:
desire_conf=C:\path\to\vivo.conf

Yeah, it must say "desire_conf", as that sentinel is build for desire, but it will work just fine!
Start sentinel-win64.exe

B) From a console, execute the EXE by passing arguments
sentinel-win64.exe --config=C:\path\to\vivo.conf

C) By creating a shortcut

1) Right click the sentinel-win64.exe, "Create Shortcut".
2) Right click the shortcut, Properties
3) Edit Target and, at the end, add a SPACE and then "--config=C:\path\to\vivo.conf" INCLUDING the quotes "

Double click the shortcut to start sentinel.

When everything fails
If you have followed all the steps and still get WATCHDOG_EXPIRED when checking masternode status:

1. Close the wallet

2. Delete all files inside "vivocore" except for "wallet.dat" and "desire.conf".
Please make sure you don't delete wallet.dat! Backup it, for real, that's your coins!

3. Restart wallet, open sentinel-win64.exe, and let it sync!