SQL Upgrade causes issues

Dreamhost is updating all of its MySQL servers to run version 8. After the upgrade, my instance of Stageshow is breaking at the point the customer clicks to pay for their tickets. They moved me to a server still running MySQL 5.7, but that option will be gone within the next month.

Has anyone else encountered this issue? Found another workaround/fix? Here’s what Dreamhost told me:
The Spencer library supports word-beginning and word-end boundary markers
([[:<:]] and [[:>:]] notation). ICU does not. For ICU, you can use \b to
match word boundaries; double the backslash because MySQL interprets it as
the escape character within strings.

They also provided me with the following:
mod_fcgid: stderr: WordPress database error Illegal argument to a
regular expression. for query SELECT * FROM wp_8ab2mf_sshow_tickets
JOIN wp_8ab2mf_sshow_sales ON
wp_8ab2mf_sshow_tickets.saleID=wp_8ab2mf_sshow_sales.saleID LEFT JOIN
wp_8ab2mf_sshow_prices ON
wp_8ab2mf_sshow_prices.priceID=wp_8ab2mf_sshow_tickets.priceID WHERE
wp_8ab2mf_sshow_prices.perfID=”196″ AND
wp_8ab2mf_sshow_sales.saleStatus != “Timeout” AND
wp_8ab2mf_sshow_sales.saleStatus != “Suspended” AND
wp_8ab2mf_sshow_tickets.ticketSeat REGEXP “[[:<:]]4_2[[:>:]]” = 1 made
by require(‘wp-blog-header.php’), require_once(‘wp-load.php’),
require_once(‘wp-config.php’), require_once(‘wp-settings.php’),
do_action(‘wp_loaded’), WP_Hook->do_action, WP_Hook->apply_filters,
StageShowPluginClass->OnlineStore_ProcessCheckout,
StageShowLibSalesPluginBaseClass->OnlineStore_ProcessCheckout,
StageShowPluginClass->IsOnlineStoreItemAvailable,
StageShowCartDBaseClass->IsSeatAvailable,
StageShowCartDBaseClass->get_results,
StageShowLibGenericDBaseClass->get_results, referer:
https://waterworksplayers.org/buytickets

https://v2uploads.zopim.io/4/8/Q/48Qbbx2RDUhgQbzIgUlRhYhlNYdCjmAn/7042
4b082b43d88e73d64a530a1fd42c64333976.jpg`

The page I need help with: [log in to see the link]