Manual-migration.php fails when going from 5.0.2 to 5.4.4

Trying to update a site to Pimcore 6 produces the following error:

Fatal error: Uncaught Error: Call to a member function initialized() on integer in ~/vendor/pimcore/pimcore/lib/Cache/Runtime.php:47
Stack trace:
#0 ~/vendor/pimcore/pimcore/lib/Cache/Runtime.php(132): Pimcore\Cache\Runtime::getInstance()
#1 ~/vendor/pimcore/pimcore/lib/Config.php(106): Pimcore\Cache\Runtime::isRegistered('pimcore_config_...')
#2 ~/vendor/pimcore/pimcore/lib/HttpKernel/Config/SystemConfigParamResource.php(53): Pimcore\Config::getSystemConfig(true)
#3 ~/vendor/pimcore/pimcore/lib/Kernel.php(103): Pimcore\HttpKernel\Config\SystemConfigParamResource->setParameters()
#4 ~/vendor/symfony/symfony/src/Symfony/Component/DependencyInjection/Loader/ClosureLoader.php(38): Pimcore\Kernel->Pimcore\{closure}(Object(Symfony\Component\DependencyInjection\ContainerBuilder))
 in ~/vendor/pimcore/pimcore/lib/Cache/Runtime.php on line 47

Our specific build we are attempting to update from is 147, following the guide here:
https://pimcore.com/docs/5.x/Development_Documentation/Installation_and_Upgrade/Upgrade_Notes/Within_V5/Update_from_5.x_to_5.4_or_above.html

We get caught on step 8. Any ideas? We don’t run into vendor library errors to frequently, not sure how to address.

Update:
Changing into DEBUG mode helped resolve this issue, however, we now encounter this error:

Warning: Use of undefined constant PIMCORE_SYMFONY_CACHE_DIRECTORY - assumed 'PIMCORE_SYMFONY_CACHE_DIRECTORY' (this will throw an Error in a future version of PHP) in ~/vendor/pimcore/pimcore/lib/Kernel.php on line 83
Warning: Use of undefined constant PIMCORE_SYMFONY_CACHE_DIRECTORY - assumed 'PIMCORE_SYMFONY_CACHE_DIRECTORY' (this will throw an Error in a future version of PHP) in ~/vendor/pimcore/pimcore/lib/Kernel.php on line 83
Warning: Use of undefined constant PIMCORE_SYMFONY_CACHE_DIRECTORY - assumed 'PIMCORE_SYMFONY_CACHE_DIRECTORY' (this will throw an Error in a future version of PHP) in ~/vendor/pimcore/pimcore/lib/Kernel.php on line 83
Warning: Use of undefined constant PIMCORE_SYMFONY_CACHE_DIRECTORY - assumed 'PIMCORE_SYMFONY_CACHE_DIRECTORY' (this will throw an Error in a future version of PHP) in ~/vendor/pimcore/pimcore/lib/Kernel.php on line 83

Fatal error: Uncaught Symfony\Component\DependencyInjection\Exception\RuntimeException: Cannot autowire service "Pimcore\Helper\LongRunningHelper": argument "$connectionRegistry" of method "__construct()" references interface "Doctrine\Common\Persistence\ConnectionRegistry" but no such service exists. It cannot be auto-registered because it is from a different root namespace. in ~/vendor/symfony/symfony/src/Symfony/Component/DependencyInjection/Compiler/DefinitionErrorExceptionPass.php:37
Stack trace:
#0 ~/vendor/symfony/symfony/src/Symfony/Component/DependencyInjection/Compiler/AbstractRecursivePass.php(60): Symfony\Component\DependencyInjection\Compiler\DefinitionErrorExceptionPass->processValue(Object(Symfony\Component\DependencyInjection\Definition), true)
#1 ~/vendor/symfony/symfony/src/Symfony/Component/DependencyInjection/Compiler/DefinitionErrorExceptionPass.php(30): Symfony\Component\Depen in ~/vendor/symfony/symfony/src/Symfony/Component/DependencyInjection/Compiler/DefinitionErrorExceptionPass.php on line 37

Any help or guidance is appreciated!